[RBAC] User and Team Role Assignment endpoints showing POST action on OPTIONS when unauthorized

[Dostonbek1]

Bug Summary

When logged in as a normal user with no roles, sending OPTIONS request on /role_user_assignments/ and role_team_assignments/ endpoints return a response that includes POST action.

Expected Behavior

Since POST action OPTIONS response is used to determine the user's ability to create a new instance of the resource, the above behavior is wrong. The expected behavior should be to show POST action to only users that have the permission to perform POST request on role assignments.