text: Title: Groups REST API - Add DELETE /api/groups/(int: id)/roles/(int: role_id)
  Body: ### Describe the problem
  
  https://docs.weblate.org/en/weblate-5.10.2/api.html#groups
  `components`, `projects`, `languages`, `componentlists`, and `admins` all have their corresponding POST and DELETE methods.
  `roles` has only POST method.
  
  ### Describe the solution you would like
  
  Add `DELETE /api/groups/(int: id)/roles/(int: role_id)`
  
  ### Describe alternatives you have considered
  
  _No response_
  
  ### Screenshots
  
  _No response_
  
  ### Additional context
  
  _No response_