Helm 3 requires SemVer 2 version compliancy of helm chart versions

Update - there was no issue

Apparently, the actual registry (https://charts.gitlab.io/index.yaml) doesn't have the v prefix in its version.

Summary

Helm chart version names are invalid SemVer 2 versions, which makes them invalid for use with Helm 3. Here are various git tags, which I assume match various versions in the helm chart repository: https://gitlab.com/gitlab-org/charts/gitlab/-/tags.

Here is some background of the issues that could surface: https://github.com/jupyterhub/chartpress/issues/86

To avoid it, this needs to be considered for the version names of Helm charts stored in a Helm chart registry.

1. They cannot be prefixed with v - ref: https://semver.org/#is-v123-a-semantic-version
2. They risk becoming invalid if a git hash is numerical and leads with a zero - ref: https://semver.org/#spec-item-2, I have avoided this by adding a prefix to git hashes, here is some discussion about doing so: https://github.com/jupyterhub/chartpress/pull/87
3. They contain a + sign, that is valid, but, helm 2 and 3 has a bug relating to this that makes use of a + sign very problematic. - ref: https://github.com/helm/helm/issues/6710