API to create self monitoring project and monitor status

What does this MR do?

1. POST API to trigger sidekiq job SelfMonitoringProjectCreateWorker. The API will return a job_id and the path of the API for checking the status of the job.

2. GET API for checking status of the above sidekiq job. This API takes the job_id as parameter and returns the output of the job if it has completed. The frontend is expected to poll this API.

Issue: #32351 (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

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