Pin github action versions

We want to enforcing action pinning. So all action versions need to be pinned.

Author: HPrinz

.github/workflows/build-push-deploy.yml

@@ -18,7 +18,7 @@ jobs:
       packages: write
     steps:
       - name: Checkout code
-        uses: actions/checkout@v6
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6
 
       - name: Login to GitHub Container Registry
         uses: docker/login-action@5e57cd118135c172c3672efd75eb46360885c0ef # v3.6.0
@@ -86,7 +86,7 @@ jobs:
     needs: build-push-image
     steps:
       - name: Deploy latest container image
-        uses: digitalservicebund/argocd-deploy@auth-token # Use the auth-token branch for STACKIT
+        uses: digitalservicebund/argocd-deploy@6033da861398e0d7fcffe1b195f8d58f10b62c4e # auth-token branch
         with:
           environment: production/gruenden-prototype2
           version: ${{ github.sha }}