login before pull

Signed-off-by: Basil Bruhn <basil.bruhn@psi.ch>

.gitea/workflows/webhosting-dmz.yaml

@@ -26,6 +26,16 @@ jobs:
     if: github.event_name == 'push' && github.ref == 'refs/heads/main'
     runs-on: webhosting_dmz
     steps:
+      - name: Log in to Gitea registry
+        env:
+          REGISTRY_USER: ${{ secrets.REGISTRY_USER }}
+          REGISTRY_TOKEN: ${{ secrets.REGISTRY_TOKEN }}
+        run: |
+          printf '%s' "$REGISTRY_TOKEN" |
+            docker login gitea.psi.ch \
+              --username "$REGISTRY_USER" \
+              --password-stdin
+
       - name: Deploy
         run: |
           set -e