Helm chart not maintained

**What happened**
The linked helm chart is not maintained anymore which limits the configuration of immudb. This prevents me from using e.g. the external storage on S3 etc.

**What you expected to happen**
Helm chart up to date with current version of immudb (Helm chart is generated for version 1.5.0)


I'd either advise to update the chart or remove it from the documentation / readme.