Update actions/checkout action to v5

Author: renovate[bot]

.github/workflows/build-test.yaml

@@ -22,7 +22,7 @@ jobs:
         os: [ubuntu-latest, windows-latest, macOS-latest]
     name: .NET Build
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v5
         with:
           fetch-depth: 0
       - name: Setup .NET