Resolve "Automatically provide a Deploy Token to projects when Auto DevOps is enabled"

What does this MR do?

Automatize the Deploy Token creation

Why was this MR needed?

When Auto DevOps is used for private or internal projects, the registry will not be accessible by Kubernetes after the deploy jobs is over. This prevents the cluster from fetching the image again in the future in case it needs it (scaling, failures, etc).

The solution is to create a Deploy Token that will be used as a permanent access to the registry.

Does this MR meet the acceptance criteria?

• Changelog entry added, if necessary
• Documentation created/updated
• API support added
• Tests added for this feature/bug
• Conform by the code review guidelines
  • Has been reviewed by a Backend maintainer
• Conform by the merge request performance guides
• Conform by the style guides
• If you have multiple commits, please combine them into a few logically organized commits by squashing them
• Internationalization required/considered
• End-to-end tests pass (package-and-qa manual pipeline job)

What are the relevant issue numbers?

Closes #46075 (closed)