Update remaining workflow files to use actions/checkout@v5

Author: brianaj

.github/workflows/copilot-setup-steps.yml

@@ -18,7 +18,7 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v5
 
       - name: Setup .NET
         uses: actions/setup-dotnet@v2

.github/workflows/integration-tests.yml

@@ -23,7 +23,7 @@ jobs:
         target-os: [windows-latest, ubuntu-latest, macos-latest]
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v4
+    - uses: actions/checkout@v5
       with:
         ref: 'refs/pull/${{ github.event.inputs.pr_number }}/merge'
         fetch-depth: 0
@@ -95,7 +95,7 @@ jobs:
     runs-on: ${{ matrix.runner-os }}
     concurrency: integration-test-${{ matrix.source-vcs }}-${{ matrix.runner-os }}
     steps:
-    - uses: actions/checkout@v4
+    - uses: actions/checkout@v5
       with:
         ref: 'refs/pull/${{ github.event.inputs.pr_number }}/merge'
         fetch-depth: 0