Fix configmap tests. Fix Helm chart pipeline

[Dean-Coakley]

Proposed changes

• Fix configmap tests behaviour was changed in: Time values have whitespace stripped and seconds have units added #1371
• Fix helm chart pipeline: As of helm 3.5.2 the helm client requires the version metadata to be a valid semver for it to be installable
• Remove helm chart sed to allow packaging of non-semver chart. It's now a semver and no longer required.

Checklist

Before creating a PR, run through this checklist and mark each as complete.

• I have read the CONTRIBUTING doc
• I have added tests that prove my fix is effective or that my feature works
• I have checked that all unit tests pass after adding my changes
• I have updated necessary documentation
• I have rebased my branch onto master
• I will ensure my PR is targeting the master branch and pulling from my branch from my own fork