This is a backport of PR #946 as merged into main (642eb93).
SUMMARY
Fix the integration test for helm_registry_auth with helm >= 3.18.0 and clarify idempotency.
Fixes#944
ISSUE TYPE
Bugfix Pull Request
COMPONENT NAME
helm_registry_auth
ADDITIONAL INFORMATION
Caused by the changes in helm starting from 3.18.0
Reviewed-by: Bianca Henderson <beeankha@gmail.com>