[PR #10505/0f7cd547 backport][stable-11] arg_spec adjustments: modules [g-j]* (#10528)

arg_spec adjustments: modules [g-j]* (#10505)

* arg_spec adjustments: modules [g-j]*

* add changelog frag

(cherry picked from commit 0f7cd5473f)

Co-authored-by: Alexei Znamensky <103110+russoz@users.noreply.github.com>

plugins/modules/gitlab_branch.py

@@ -118,7 +118,7 @@ def main():
     argument_spec.update(
         project=dict(type='str', required=True),
         branch=dict(type='str', required=True),
-        ref_branch=dict(type='str', required=False),
+        ref_branch=dict(type='str'),
         state=dict(type='str', default="present", choices=["absent", "present"]),
     )