Update actions/checkout action to v6

Author: renovate[bot]

.github/workflows/main_bod-roadmapreport.yml

@@ -14,7 +14,7 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@8e8c483db84b4bee98b60c0593521ed34d9990e8 # v6
 
       - name: Set up .NET Core
         uses: actions/setup-dotnet@v4