Make Auto DevOps alert dismissible in Security Configuration page

What does this MR do?

Makes the Auto DevOps alert in Security Configuration dismissible. Addresses #239468 (closed).

Screenshots

Before	After	After and dismissed

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