Introduce rate limit for creating issues via API

What does this MR do?

https://gitlab.com/gitlab-org/gitlab/-/issues/55241

Adds a rate limit of 300/minute for the API endpoint POST /api/v4/projects/:id/issues

I've added the limit to the controller and the option to set this values through the Settings page here -> !28129 (merged)

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