Use pull_request_target

Signed-off-by: Fredrik Lönnegren <fredrik.lonnegren@suse.com>

.github/workflows/build_and_test_x86.yaml

@@ -23,6 +23,8 @@ jobs:
       REPO: ghcr.io/${{ github.repository }}/elemental-${{ inputs.flavor }}
     steps:
       - uses: actions/checkout@v4
+        with:
+          ref: "${{ github.event.pull_request.merge_commit_sha }}"
       - run: |
           git fetch --prune --unshallow
       - name: Log in to registry
@@ -50,6 +52,8 @@ jobs:
       REPO: ghcr.io/${{ github.repository }}/elemental-${{ inputs.flavor }}
     steps:
       - uses: actions/checkout@v4
+        with:
+          ref: "${{ github.event.pull_request.merge_commit_sha }}"
       - run: |
           git fetch --prune --unshallow
       - name: Cached ISO
@@ -87,6 +91,8 @@ jobs:
       ARCH: x86_64
     steps:
       - uses: actions/checkout@v4
+        with:
+          ref: "${{ github.event.pull_request.merge_commit_sha }}"
       - run: |
           git fetch --prune --unshallow
       - name: Checks cached Disk
@@ -152,6 +158,8 @@ jobs:
       fail-fast: false
     steps:
       - uses: actions/checkout@v4
+        with:
+          ref: "${{ github.event.pull_request.merge_commit_sha }}"
       - name: Install Go
         uses: actions/setup-go@v5
         with:
@@ -209,6 +217,8 @@ jobs:
       COS_TIMEOUT: 1600
     steps:
       - uses: actions/checkout@v4
+        with:
+          ref: "${{ github.event.pull_request.merge_commit_sha }}"
       - name: Install Go
         uses: actions/setup-go@v5
         with:

.github/workflows/pr.yaml

@@ -1,6 +1,6 @@
 name: PR
 on:
-  pull_request:
+  pull_request_target:
     paths:
       - tests/**
       - make/**
@@ -35,6 +35,8 @@ jobs:
       TOOLKIT_REPO: ghcr.io/${{github.repository}}/elemental-cli 
     steps:
       - uses: actions/checkout@v4
+        with:
+          ref: "${{ github.event.pull_request.merge_commit_sha }}"
       - run: |
           git fetch --prune --unshallow
       - name: Log in to ghcr.io