no changelog in helm chart included

**Is your feature request related to a problem? Please describe.**

the helm chart seems not to include a CHANGELOG note

quick check:
artifacthub.io shows CHANGELOG if available:

pulsar: no CHANGELOG
https://artifacthub.io/packages/helm/apache/pulsar

example with included CHANGELOG
Apache Airflow
https://artifacthub.io/packages/helm/apache-airflow/airflow?modal=changelog

**Describe the solution you'd like**
ad CHANGELOG to helm chart

background: https://helm.sh/docs/topics/charts/#chart-license-readme-and-notes

**Describe alternatives you've considered**
none

**Additional context**
none