Remove def _helm_chart_dir that used undefined env var

[viveksinghggits]

Summary

In our source file we had a function

def _helm_chart_dir(default: Optional[str] = "helm_chart") -> str:
    return os.environ.get("HELM_CHART_DIR", default)

The env var HELM_CHART_DIR is not set in our project anywhere that makes this function not needed. That's why this PR removes the function.

From the function def we can see that it would always return what was passed to this function, that's why at the caller we are removing the function call and just using the argument.

Proof of Work

CI in the PR.

Checklist

• Have you linked a jira ticket and/or is the ticket in the title?
• Have you checked whether your jira ticket required DOCSP changes?
• Have you added changelog file?
  • use skip-changelog label if not needed
  • refer to Changelog files and Release Notes section in CONTRIBUTING.md for more details

[github-actions]

⚠️ (this preview might not be accurate if the PR is not rebased on current master branch)

MCK 1.6.0 Release Notes

New Features

• MongoDBCommunity: Added support to configure custom cluster domain via newly introduced spec.clusterDomain resource field. If spec.clusterDomain is not set, environment variable CLUSTER_DOMAIN is used as cluster domain. If the environment variable CLUSTER_DOMAIN is also not set, operator falls back to cluster.local as default cluster domain.
• Helm Chart: Introduced two new helm fields operator.podSecurityContext and operator.securityContext that can be used to configure securityContext for Operator deployment through Helm Chart.

Bug Fixes

• Fixed parsing of the customEnvVars Helm value when values contain = characters.