align the login username with the namespace

Author: myk002

.github/workflows/container-build.yml

@@ -21,7 +21,7 @@ jobs:
       uses: docker/login-action@v3
       with:
         registry: ghcr.io
-        username: ${{ github.actor }}
+        username: ${{ env.GHCR_NAMESPACE }}
         password: ${{ secrets.GITHUB_TOKEN }}
     - name: Build and push
       uses: docker/build-push-action@v6