Use `helm dependency build` in release build (#563)

Using `helm dependency update` may result in unwillingly updating the
dependencies while cutting a release. I wasn't able to do so. Most
likely due to the dependency pinning in Chart.yaml and Chart.lock.

Based on Helm documentation, `update` uses Chart.yaml[^1] while `build`
uses Chart.lock[^2].
All in all it is safer to use `helm dependency build`. :D

[^1]: https://helm.sh/docs/helm/helm_dependency_update/
[^2]: https://helm.sh/docs/helm/helm_dependency_build/

Reviewed-on: https://gitea.com/gitea/helm-chart/pulls/563
Reviewed-by: pat-s <pat-s@noreply.gitea.com>

.gitea/workflows/release-version.yml

@@ -44,7 +44,7 @@ jobs:
           echo ${{ secrets.DOCKER_CHARTS_PASSWORD }} | docker login -u ${{ secrets.DOCKER_CHARTS_USERNAME }} --password-stdin
           # FIXME: use upstream after https://github.com/technosophos/helm-gpg/issues/1 is solved
           helm plugin install https://github.com/pat-s/helm-gpg
-          helm dependency update
+          helm dependency build
           helm package --version "${GITHUB_REF#refs/tags/v}" ./
           helm gpg sign "gitea-${GITHUB_REF#refs/tags/v}.tgz"
           mkdir gitea