Improving error handling in SecretManager

[aishwaryabh]

Issue describing the changes in this PR

This PR improves error handling in the Secret manager so that if there's a race condition (ie multiple secret repositories are created, each try to create their own version of a secret, and whichever one actually creates it first succeeds and the rest error out). If an error happens with WriteAsync, we simply call LoadSecretsAsync first before failing and throwing an exception to make sure the issue is not a race condition

resolves #8731

Pull request checklist

• My changes do not require documentation changes
  • Otherwise: Documentation issue linked to PR
• My changes should not be added to the release notes for the next release
  • Otherwise: I've added my notes to release_notes.md
• My changes do not need to be backported to a previous version
  • Otherwise: Backport tracked by issue/PR #issue_or_pr
• My changes do not require diagnostic events changes
  • Otherwise: I have added/updated all related diagnostic events and their documentation (Documentation issue linked to PR)
• I have added all required tests (Unit tests, E2E tests)

Additional information

Additional PR information

[brettsam]

Just a couple comments on the error messages...