Description

Added a note on idempotency for the storage group module.

GitHub Issues

List the GitHub issues impacted by this PR:

GitHub Issue #

[X] I have performed a self-review of my own code to ensure there are no formatting, pep8, linting, or security issues
[X] I have performed Ansible Sanity test using --docker default
[X] I have verified that new and existing unit tests pass locally with my changes
[X] I have not allowed coverage numbers to degenerate
[ ] I have maintained at least 90% code coverage
[X] I have commented my code, particularly in hard-to-understand areas
[X] I have made corresponding changes to the documentation
[X] I have added tests that prove my fix is effective or that my feature works
[X] Backward compatibility is not broken

Please describe the tests that you ran to verify your changes. Please also list any relevant details for your test configuration