Add alert for autodevops policies to the Policy list

What does this MR do?

This commit adds a new alert for policies managed by Auto DevOps pipelines to the Policies Tab of the Threat Monitoring page. This alert is only visible if at least one Auto DevOps policy is present.

This alert is meant to assist Auto DevOps users migrating to the new Network Policy UI.

This MR is a part of ongoing work for the new Policy Management UI (&3328 (closed))

Related backend changes: !32715 (merged)

Screenshots

With AutoDevOps policy	Without AutoDevOps policy

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