Add password expiration to application settings on backend

What does this MR do and why?

This mr is to do support for password expiration settings on backend.

• Add validates for password expiration settings migration.
• Support api/v4 GET/UPDATE for password expiration settings.

get: GET {GDK}/api/v4/application/settings

update: PUT {GDK}/api/v4/application/settings

• Support UI GET/UPDATE backend for password expiration settings.
• Make password expiration only available in Starter, Premium and Ultimate .

License feature name: password_expiration

• Add feature flag to password expiration feature.

Feature flag name: password_expiration

The migration MR of related attributes: https://gitlab.com/gitlab-org/gitlab/-/merge_requests/100519

The translation part of this MR has been certified by @shuangzhang .

Screenshots or screen recordings

API test screenshots:

	Before	After
Get
Update

How to set up and validate locally

Numbered steps to set up and validate the change are strongly suggested.

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.

Closes #1926 (closed)