Description of the problem, including code/CLI snippet

Options related to squash are not available when merging the merge request

Expected Behavior

All options available in the API should be available as parameters

Actual Behavior

Only merge_commit_message, should_remove_source_branch and merge_when_pipeline_succeeds are available. The options sha, squash_commit_message and squash are missing.

Specifications

• python-gitlab version: 3.3.0
• API version you are using (v3/v4): v4
• Gitlab server version (or gitlab.com): gitlab.com

I checked the code and in thegitlab.v4.objects.ProjectMergeRequest.merge method, the kwargs are ignored. Only 3 hardcoded options are being used.