Allow the Gitea image through the dockerhub remote

The k8s Gitea deployment pulls gitea/gitea (rootless) from Docker Hub via the
artifactapi mirror. Add it to the dockerhub allowlist.

- add "^gitea/gitea" to config/remote_docker/dockerhub.yaml patterns

Claude-Session: https://claude.ai/code/session_015ur3i7D2azsMAWTSVABApv

config/remote_docker/dockerhub.yaml

@@ -19,6 +19,7 @@ patterns:
   - "^clickhouse/"
   - "^curlimages/curl"
   - "^emberstack/kubernetes-reflector"
+  - "^gitea/gitea"
   - "^grafana/"
   - "^hashicorp/consul"
   - "^hashicorp/vault"