Improve Container Registry UI Header

What does this MR do?

This MR improves and changes the Container Registry List header in the following way:

• removed the big expiration policy banner
• added sub-title section with the total amount of images and expiration policy execution/status
• added an option description text when the expiration policy is disabled
• changes quick start to CLI commands

Screenshots

Exp policy Disabled	Exp policy Enabled	Empty Container Registry	Group Level

note: the expiration policy message uses a 'time utility' that starts from weeks then goes down to days then to hours and minutes like so:

Does this MR meet the acceptance criteria?

Conformity

• Changelog entry
• Documentation (if required)
• Code review guidelines
• Merge request performance guidelines
• Style guides
• [-] Database guides
• [-] Separation of EE specific content

Availability and Testing

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• Tested in all supported browsers
• [-] Informed Infrastructure department of a default or new setting change, if applicable per definition of done

Security

If this MR contains changes to processing or storing of credentials or tokens, authorization and authentication methods and other items described in the security review guidelines:

• [-] Label as security and @ mention @gitlab-com/gl-security/appsec
• [-] The MR includes necessary changes to maintain consistency between UI, API, email, or other methods
• [-] Security reports checked/validated by a reviewer from the AppSec team

Part of #216749 (closed)