Limit resource access tokens to paid GitLab.com plans

What does this MR do?

Related to https://gitlab.com/gitlab-org/gitlab/-/issues/220220

resource_access_token becomes a licensed feature instead of a development feature flag. The feature is available in Core for self-managed and on paid, non-trial groups/projects for .com. This distinction is to lower abuse on GitLab.com.

This also moves the feature availability from adhoc checks to a policy. This centralizes the logic and makes it less likely that the feature will be erroneously enabled for a given user, group or project.

NOTE: Event with these changes this is not yet in effect until #235765 (closed) is done. #235765 (closed) should update documentation/badges in documentation accordingly.

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

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