Description of the problem, including code/CLI snippet

Feature/improve suggestion: in many of my cases, I would like to have an autocompletion to have less time to spend at docs and source code to find out all possible combination of commands/object/args.

Expected Behavior

Would be great to have autocompletion for bash or zsh.

Actual Behavior

No completion right now.

Specifications

• python-gitlab version: 1.6.0
• API version you are using (v3/v4): 4
• Gitlab server version (or gitlab.com): gitlab.com