feat(helm): Helm support OpenStack application credentials for Swift storage

[heytrav]

What this PR does / why we need it:

Support application credentials for authentication with OpenStack.

Which issue(s) this PR fixes:

#14034

Special notes for your reviewer:

Checklist

• Reviewed the CONTRIBUTING.md guide (required)
• Documentation added
• Tests updated
• Title matches the required conventional commits format, see here
  • Note that Promtail is considered to be feature complete, and future development for logs collection will be in Grafana Alloy. As such, feat PRs are unlikely to be accepted unless a case can be made for the feature actually being a bug fix to existing behavior.
• Changes that require user attention or interaction to upgrade are documented in docs/sources/setup/upgrade/_index.md
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[heytrav]

From what I could see in the code I believe the arguments should go into the gopher cloud module as written and the password field becomes optional.

Please let me know if I've missed something though.

[heytrav]

Is there something I still need to do to get this reviewed?

[CLAassistant]

Thank you for your submission! We really appreciate it. Like many open source projects, we ask that you sign our Contributor License Agreement before we can accept your contribution.

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