feat(ec2): default BastionHostLinux to use Amazon Linux 2023 (under f…

…eature flag) (#31996)

### Issue #29493

Closes #29493

### Reason for this change

Right now, if a `machineImage` property isn't passed to `BastionHostLinux`, it defaults to an Amazon Linux 2 image. Since Amazon Linux 2 is hitting end-of-life in June 2025, it'd be better to default to Amazon Linux 2023.

Since changing this default would be a breaking change, I placed it behind a feature flag, `@aws-cdk/aws-ec2:bastionHostUseAmazonLinux2023ByDefault`.

### Description of changes

- Added the `@aws-cdk/aws-ec2:bastionHostUseAmazonLinux2023ByDefault`
- When set, and a `machineImage` is not provided, we use the latest Amazon Linux 2023 image, instead of Amazon Linux 2.

### Description of how you validated changes

- Unit Tests
- Integration Test

### Checklist
- [x] My code adheres to the [CONTRIBUTING GUIDE](https://github.com/aws/aws-cdk/blob/main/CONTRIBUTING.md) and [DESIGN GUIDELINES](https://github.com/aws/aws-cdk/blob/main/docs/DESIGN_GUIDELINES.md)

----

*By submitting this pull request, I confirm that my contribution is made under the terms of the Apache-2.0 license*

packages/@aws-cdk-testing/framework-integ/test/aws-ec2/test/integ.bastion-host-arm-support.js.snapshot/TestStack.template.json

@@ -18,9 +18,6 @@
   "VPCPublicSubnet1SubnetB4246D30": {
    "Type": "AWS::EC2::Subnet",
    "Properties": {
-    "VpcId": {
-     "Ref": "VPCB9E5F0B4"
-    },
     "AvailabilityZone": {
      "Fn::Select": [
       0,
@@ -44,21 +41,24 @@
       "Key": "Name",
       "Value": "TestStack/VPC/PublicSubnet1"
      }
-    ]
+    ],
+    "VpcId": {
+     "Ref": "VPCB9E5F0B4"
+    }
    }
   },
   "VPCPublicSubnet1RouteTableFEE4B781": {
    "Type": "AWS::EC2::RouteTable",
    "Properties": {
-    "VpcId": {
-     "Ref": "VPCB9E5F0B4"
-    },
     "Tags": [
      {
       "Key": "Name",
       "Value": "TestStack/VPC/PublicSubnet1"
      }
-    ]
+    ],
+    "VpcId": {
+     "Ref": "VPCB9E5F0B4"
+    }
    }
   },
   "VPCPublicSubnet1RouteTableAssociation0B0896DC": {
@@ -75,12 +75,12 @@
   "VPCPublicSubnet1DefaultRoute91CEF279": {
    "Type": "AWS::EC2::Route",
    "Properties": {
-    "RouteTableId": {
-     "Ref": "VPCPublicSubnet1RouteTableFEE4B781"
-    },
     "DestinationCidrBlock": "0.0.0.0/0",
     "GatewayId": {
      "Ref": "VPCIGWB7E252D3"
+    },
+    "RouteTableId": {
+     "Ref": "VPCPublicSubnet1RouteTableFEE4B781"
     }
    },
    "DependsOn": [
@@ -102,15 +102,15 @@
   "VPCPublicSubnet1NATGatewayE0556630": {
    "Type": "AWS::EC2::NatGateway",
    "Properties": {
-    "SubnetId": {
-     "Ref": "VPCPublicSubnet1SubnetB4246D30"
-    },
     "AllocationId": {
      "Fn::GetAtt": [
       "VPCPublicSubnet1EIP6AD938E8",
       "AllocationId"
      ]
     },
+    "SubnetId": {
+     "Ref": "VPCPublicSubnet1SubnetB4246D30"
+    },
     "Tags": [
      {
       "Key": "Name",
@@ -126,9 +126,6 @@
   "VPCPublicSubnet2Subnet74179F39": {
    "Type": "AWS::EC2::Subnet",
    "Properties": {
-    "VpcId": {
-     "Ref": "VPCB9E5F0B4"
-    },
     "AvailabilityZone": {
      "Fn::Select": [
       1,
@@ -152,21 +149,24 @@
       "Key": "Name",
       "Value": "TestStack/VPC/PublicSubnet2"
      }
-    ]
+    ],
+    "VpcId": {
+     "Ref": "VPCB9E5F0B4"
+    }
    }
   },
   "VPCPublicSubnet2RouteTable6F1A15F1": {
    "Type": "AWS::EC2::RouteTable",
    "Properties": {
-    "VpcId": {
-     "Ref": "VPCB9E5F0B4"
-    },
     "Tags": [
      {
       "Key": "Name",
       "Value": "TestStack/VPC/PublicSubnet2"
      }
-    ]
+    ],
+    "VpcId": {
+     "Ref": "VPCB9E5F0B4"
+    }
    }
   },
   "VPCPublicSubnet2RouteTableAssociation5A808732": {
@@ -183,12 +183,12 @@
   "VPCPublicSubnet2DefaultRouteB7481BBA": {
    "Type": "AWS::EC2::Route",
    "Properties": {
-    "RouteTableId": {
-     "Ref": "VPCPublicSubnet2RouteTable6F1A15F1"
-    },
     "DestinationCidrBlock": "0.0.0.0/0",
     "GatewayId": {
      "Ref": "VPCIGWB7E252D3"
+    },
+    "RouteTableId": {
+     "Ref": "VPCPublicSubnet2RouteTable6F1A15F1"
     }
    },
    "DependsOn": [
@@ -210,15 +210,15 @@
   "VPCPublicSubnet2NATGateway3C070193": {
    "Type": "AWS::EC2::NatGateway",
    "Properties": {
-    "SubnetId": {
-     "Ref": "VPCPublicSubnet2Subnet74179F39"
-    },
     "AllocationId": {
      "Fn::GetAtt": [
       "VPCPublicSubnet2EIP4947BC00",
       "AllocationId"
      ]
     },
+    "SubnetId": {
+     "Ref": "VPCPublicSubnet2Subnet74179F39"
+    },
     "Tags": [
      {
       "Key": "Name",
@@ -234,9 +234,6 @@
   "VPCPrivateSubnet1Subnet8BCA10E0": {
    "Type": "AWS::EC2::Subnet",
    "Properties": {
-    "VpcId": {
-     "Ref": "VPCB9E5F0B4"
-    },
     "AvailabilityZone": {
      "Fn::Select": [
       0,
@@ -260,21 +257,24 @@
       "Key": "Name",
       "Value": "TestStack/VPC/PrivateSubnet1"
      }
-    ]
+    ],
+    "VpcId": {
+     "Ref": "VPCB9E5F0B4"
+    }
    }
   },
   "VPCPrivateSubnet1RouteTableBE8A6027": {
    "Type": "AWS::EC2::RouteTable",
    "Properties": {
-    "VpcId": {
-     "Ref": "VPCB9E5F0B4"
-    },
     "Tags": [
      {
       "Key": "Name",
       "Value": "TestStack/VPC/PrivateSubnet1"
      }
-    ]
+    ],
+    "VpcId": {
+     "Ref": "VPCB9E5F0B4"
+    }
    }
   },
   "VPCPrivateSubnet1RouteTableAssociation347902D1": {
@@ -291,21 +291,18 @@
   "VPCPrivateSubnet1DefaultRouteAE1D6490": {
    "Type": "AWS::EC2::Route",
    "Properties": {
-    "RouteTableId": {
-     "Ref": "VPCPrivateSubnet1RouteTableBE8A6027"
-    },
     "DestinationCidrBlock": "0.0.0.0/0",
     "NatGatewayId": {
      "Ref": "VPCPublicSubnet1NATGatewayE0556630"
+    },
+    "RouteTableId": {
+     "Ref": "VPCPrivateSubnet1RouteTableBE8A6027"
     }
    }
   },
   "VPCPrivateSubnet2SubnetCFCDAA7A": {
    "Type": "AWS::EC2::Subnet",
    "Properties": {
-    "VpcId": {
-     "Ref": "VPCB9E5F0B4"
-    },
     "AvailabilityZone": {
      "Fn::Select": [
       1,
@@ -329,21 +326,24 @@
       "Key": "Name",
       "Value": "TestStack/VPC/PrivateSubnet2"
      }
-    ]
+    ],
+    "VpcId": {
+     "Ref": "VPCB9E5F0B4"
+    }
    }
   },
   "VPCPrivateSubnet2RouteTable0A19E10E": {
    "Type": "AWS::EC2::RouteTable",
    "Properties": {
-    "VpcId": {
-     "Ref": "VPCB9E5F0B4"
-    },
     "Tags": [
      {
       "Key": "Name",
       "Value": "TestStack/VPC/PrivateSubnet2"
      }
-    ]
+    ],
+    "VpcId": {
+     "Ref": "VPCB9E5F0B4"
+    }
    }
   },
   "VPCPrivateSubnet2RouteTableAssociation0C73D413": {
@@ -360,12 +360,12 @@
   "VPCPrivateSubnet2DefaultRouteF4F5CFD2": {
    "Type": "AWS::EC2::Route",
    "Properties": {
-    "RouteTableId": {
-     "Ref": "VPCPrivateSubnet2RouteTable0A19E10E"
-    },
     "DestinationCidrBlock": "0.0.0.0/0",
     "NatGatewayId": {
      "Ref": "VPCPublicSubnet2NATGateway3C070193"
+    },
+    "RouteTableId": {
+     "Ref": "VPCPrivateSubnet2RouteTable0A19E10E"
     }
    }
   },
@@ -383,11 +383,11 @@
   "VPCVPCGW99B986DC": {
    "Type": "AWS::EC2::VPCGatewayAttachment",
    "Properties": {
-    "VpcId": {
-     "Ref": "VPCB9E5F0B4"
-    },
     "InternetGatewayId": {
      "Ref": "VPCIGWB7E252D3"
+    },
+    "VpcId": {
+     "Ref": "VPCB9E5F0B4"
     }
    }
   },
@@ -486,7 +486,7 @@
      "Ref": "BastionHostInstanceProfile770FCA07"
     },
     "ImageId": {
-     "Ref": "SsmParameterValueawsserviceamiamazonlinuxlatestamzn2amikernel510hvmarm64gp2C96584B6F00A464EAD1953AFF4B05118Parameter"
+     "Ref": "SsmParameterValueawsserviceamiamazonlinuxlatestal2023amikernel61arm64C96584B6F00A464EAD1953AFF4B05118Parameter"
     },
     "InstanceType": "t4g.nano",
     "SecurityGroupIds": [
@@ -525,9 +525,9 @@
   }
  },
  "Parameters": {
-  "SsmParameterValueawsserviceamiamazonlinuxlatestamzn2amikernel510hvmarm64gp2C96584B6F00A464EAD1953AFF4B05118Parameter": {
+  "SsmParameterValueawsserviceamiamazonlinuxlatestal2023amikernel61arm64C96584B6F00A464EAD1953AFF4B05118Parameter": {
    "Type": "AWS::SSM::Parameter::Value<AWS::EC2::Image::Id>",
-   "Default": "/aws/service/ami-amazon-linux-latest/amzn2-ami-kernel-5.10-hvm-arm64-gp2"
+   "Default": "/aws/service/ami-amazon-linux-latest/al2023-ami-kernel-6.1-arm64"
   },
   "BootstrapVersion": {
    "Type": "AWS::SSM::Parameter::Value<String>",