storage: Set the default LUKS version for interactive partitioning

During the interactive partititioning (via the Custom Partitioning GUI screen),
make sure that the LUKS version is set to the default one instead of None.

pyanaconda/modules/storage/partitioning/interactive/utils.py

@@ -604,6 +604,7 @@ def change_encryption(storage, device, encrypted, luks_version):
         return device.raw_device
     else:
         log.info("Applying encryption to %s.", device.name)
+        luks_version = luks_version or storage.default_luks_version
         new_fmt = get_format("luks", device=device.path, luks_version=luks_version)
         storage.format_device(device, new_fmt)
         luks_dev = LUKSDevice("luks-" + device.name, parents=[device])
@@ -778,7 +779,7 @@ def get_device_factory_arguments(storage, request: DeviceFactoryRequest, subset=
         "mountpoint": request.mount_point or None,
         "fstype": request.format_type or None,
         "label": request.label or None,
-        "luks_version": request.luks_version or None,
+        "luks_version": request.luks_version or storage.default_luks_version,
         "device_name": request.device_name or None,
         "size": Size(request.device_size) or None,
         "raid_level": get_raid_level_by_name(request.device_raid_level),

tests/unit_tests/pyanaconda_tests/modules/storage/partitioning/test_module_part_interactive.py

@@ -383,7 +383,7 @@ def test_get_device_factory_arguments(self):
             "fstype": None,
             "label": None,
             "encrypted": False,
-            "luks_version": None,
+            "luks_version": "luks2",
             "raid_level": None,
             "container_name": "container1",
             "container_size": Size("10 GiB"),