chore(deps): update actions/checkout action to v4

Author: renovate[bot]

.github/workflows/ci.yml

@@ -14,7 +14,7 @@ jobs:
     name: Code
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@3df4ab11eba7bda6032a0b82a6bb43b11571feac # v4
     - name: Build Solution
       run: dotnet build src/Promitor.DataGeneration.sln --configuration Release
   bicep: