Allows JH to independently control the feature license level

Issue link

#727 (closed)

Dependency

Upstream MR:

• https://gitlab.com/gitlab-org/gitlab/-/merge_requests/83263 Merged
• https://gitlab.com/gitlab-org/gitlab/-/merge_requests/85764 Merged

Proposal

Add prepend methods to Features and License to let JH read the new license configuration.

• project level check
• namespace level check
• global level check

The core method is licensed_feature_available? (feature_available?).

How to test

Ensure that previous behavior is unchanged

• Users with low level license can not use high level features
• Users with license can use current license level features

Ensure that new behavior is expected

• JH customized license takes effect.

In Upstream, external_audit_events is in Ultimate level; in JH, it's in Premium level.

Reference

https://docs.gitlab.com/ee/development/licensed_feature_availability.html

https://docs.gitlab.com/ee/subscriptions