Description of the problem, including code/CLI snippet

I can't thank you enough for making the library, its very very helpful.

Would it be possible to add the functionality to get/remove the billable membership through this library as well?

Expected Behavior

Functionality not available.

Actual Behavior

Be able to get the billable members or remove any billable member to take away the seat

Specifications

• python-gitlab version: latest
• API version you are using (v3/v4): v4
• Gitlab server version (or gitlab.com):