Fix registry secret name in build workflow

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

.gitea/workflows/docker-build.yml

@@ -26,7 +26,7 @@ jobs:
         with:
           registry: ${{ env.REGISTRY }}
           username: ${{ secrets.REGISTRY_USERNAME }}
-          password: ${{ secrets.REGISTRY_PASSWORD }}
+          password: ${{ secrets.REGISTRY_TOKEN }}
 
       - name: Extract metadata
         id: meta