Add Spec For Ci Cd Controller

What does this MR do?

Add a spec for the Projects::Settings::CiCdController#update action. Test the interface between the invoked CreatePipelineWorker and the Ci::CreatePipelineService#execute method.

This WIP MR (!28366 (closed)) demonstrates a gap in testing around changing parameters to Ci::CreatePipelineService#execute.

The mistake marked with a comment here: !28366 (diffs)

Is caught only by the additional spec here: !28366 (diffs)

This MR adds the spec that catches the mistake.

Related to #30111 (closed)

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