Helm chartmuseum push plugin is not working with Helm v4 on helm-toolbox 1.2.0
I observed this pipeline [failure](https://gitlab.com/sylva-projects/sylva-elements/helm-charts/metallb-resources/-/jobs/14549403845#L34), that prevents new metallb-rosources helm chart tags from being pushed on Helm chart repository server https://gitlab.com/api/v4/projects/62761003/packages/helm/base.
```
$ helm cm-push ${CHART}*.tgz ${CHART}
Error: unknown command "cm-push" for "helm"
```
This is blocking metallb-resources version bump [MR](https://gitlab.com/sylva-projects/sylva-core/-/merge_requests/7978) because the first CP node cannot install `0.3.0` metallb-resources version:
```
+ helm repo add metallb-resources https://gitlab.com/api/v4/projects/62761003/packages/helm/base
...
+ helm install --namespace metallb-system --version 0.3.0 metallb-resources metallb-resources/metallb-resources --values /config/values-0-000-HelmChart-ValuesContent.yaml
Error: INSTALLATION FAILED: chart "metallb-resources" matching 0.3.0 not found in metallb-resources index. (try 'helm repo update'): no chart version found for metallb-resources-0.3.0
```
Cause seem to be related to [upgrading](https://gitlab.com/sylva-projects/sylva-elements/container-images/helm-toolbox/-/merge_requests/165) Helm to v4, in which support for plugins is limited - I found a similar upstream [issue](https://github.com/helm/helm/issues/31534).
`0.11.1` [chartmuseum version](https://gitlab.com/sylva-projects/sylva-elements/container-images/helm-toolbox/-/blob/main/Dockerfile?ref_type=heads#L13) seems to be compatible to Helm v4, implemented in upstream issue: https://github.com/chartmuseum/helm-push/issues/225
I think having helm-toolbox bumped to `1.2.1` in [ci-tooling](https://gitlab.com/sylva-projects/sylva-elements/ci-tooling/ci-templates/-/blob/main/templates/helm-tooling.yml?ref_type=heads#L11) should fix this, but I did not find any renovate MR for this.
Or a quicker workaround to unblock metallb-resources version bump [MR](https://gitlab.com/sylva-projects/sylva-core/-/merge_requests/7978) would be to temporary revert [metallb-resources ci-tooling/ci-templates change](https://gitlab.com/sylva-projects/sylva-elements/helm-charts/metallb-resources/-/merge_requests/82) and push the helm chart tag by using Helm v3.
issue