feat!: upstream changes (#47)

GPG feature has breaking changes

Co-authored-by: robv89r <robv8r@noreply.gitea.io>
Co-authored-by: justusbunsi <justusbunsi@noreply.gitea.io>
Co-authored-by: Michael Kriese <michael.kriese@visualon.de>
Reviewed-on: https://codeberg.org/forgejo-contrib/forgejo-helm/pulls/47

CONTRIBUTING.md

@@ -50,3 +50,13 @@ be used:
    forwarded first from `minikube` to localhost first via `kubectl --namespace
    default port-forward svc/gitea-http 3000:3000`. Now Gitea is accessible at
    [http://localhost:3000](http://localhost:3000).
+
+### Unit tests
+
+```bash
+# install the unittest plugin
+$ helm plugin install https://github.com/heyhabito/helm-unittest
+
+# run the unittests
+make unittests
+```