Warning messages for pipeline configurations

What does this MR do?

• Adds a warning message to the CI lint view
• Adds a warning message to the pipeline view
• Adds a warning message to the run new pipeline view

Currently behind feature flag ci_raise_job_rules_without_workflow_rules_warning. Should not merge until the feature flag has been flipped on here !38712 (merged)

You will need to enable the feature flag locally to test Feature.enable(:ci_raise_job_rules_without_workflow_rules_warning)

Related to: #219431 (closed)

Screenshots

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