fix(codepipeline-actions): default branch for CodeCommit is master (under feature flag) (#27753)

Closes #27710.

----

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

Author: daschaa

packages/@aws-cdk-testing/framework-integ/test/aws-codepipeline-actions/test/integ.cfn-template-from-repo.lit.js.snapshot/aws-cdk-codepipeline-cloudformation.assets.json

@@ -249,6 +249,21 @@
   "PipelineC660917D": {
    "Type": "AWS::CodePipeline::Pipeline",
    "Properties": {
+    "ArtifactStore": {
+     "EncryptionKey": {
+      "Id": {
+       "Fn::GetAtt": [
+        "PipelineArtifactsBucketEncryptionKey01D58D69",
+        "Arn"
+       ]
+      },
+      "Type": "KMS"
+     },
+     "Location": {
+      "Ref": "PipelineArtifactsBucket22248F97"
+     },
+     "Type": "S3"
+    },
     "RoleArn": {
      "Fn::GetAtt": [
       "PipelineRoleD68726F7",
@@ -272,7 +287,7 @@
            "Name"
           ]
          },
-         "BranchName": "master",
+         "BranchName": "main",
          "PollForSourceChanges": true
         },
         "Name": "Source",
@@ -368,22 +383,7 @@
       ],
       "Name": "Deploy"
      }
-    ],
-    "ArtifactStore": {
-     "EncryptionKey": {
-      "Id": {
-       "Fn::GetAtt": [
-        "PipelineArtifactsBucketEncryptionKey01D58D69",
-        "Arn"
-       ]
-      },
-      "Type": "KMS"
-     },
-     "Location": {
-      "Ref": "PipelineArtifactsBucket22248F97"
-     },
-     "Type": "S3"
-    }
+    ]
    },
    "DependsOn": [
     "PipelineRoleDefaultPolicyC7A05455",