fix(ci): replace pull_request ref_name by commit sha

Author: import-benjamin

.github/workflows/go.yml

@@ -21,7 +21,7 @@ jobs:
       uses: redhat-actions/buildah-build@7a95fa7ee0f02d552a32753e7414641a04307056
       with:
         image: ghcr.io/${{ github.repository }}
-        tags: ${{ github.ref_name }}
+        tags: ${{ github.event_type == 'push' && github.ref_name || github.sha }}
         containerfiles: |
           ./Containerfile
         extra-args: |