New REST api endpoint to fetch CI_JOB_TOKEN access settings

What does this MR do and why?

This MR works towards the first task of the issue (feature) #351740 (closed) .

🛠 with ❤ at Siemens

Screenshots or screen recordings

Here is the reponse when requesting the new api endpoint, see http://127.0.0.1:3000/api/v4/projects/7/job_token_scope

{
	"inbound_enabled": true,
	"outbound_enabled": false
}

How to set up and validate locally

1. Create a personal access token with the respective rights
2. Ensure the user of the personal access token is at least maintainer of the project
3. Execute the following curl command

curl --request GET \
  --url http://127.0.0.1:3000/api/v4/projects/7/job_token_scope?private_token=<personal_access_token_of_project_maintainer>

TODO

• Ensure correct permissions for request, i.e. maintainer or higher, see #351740 (closed)
• Add test
• Check if there are other properties that should be exposed in the response
• Check if the right error codes are returned
• Check for correct configuration in openapi.yml
• Check if the personal access token need to have admin_mode
• Add tests to new entity

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.

• Changelog entry added, if necessary

• [-] Documentation created/updated via this MR

• Documentation reviewed by technical writer or follow-up review issue created

• Tests added for this feature/bug

• Tested in all supported browsers

• Conforms to the code review guidelines

• Conforms to the merge request performance guidelines

• Conforms to the style guides

• [-] Conforms to the javascript style guides

• [-] Conforms to the database guides

Related to #351740 (closed)