code: func (g *Gitlab) EditMergeRequest(mr *MergeRequest) error {
  	u := g.ResourceUrl(ProjectMergeRequestApiPath, map[string]string{
  		":id":                string(mr.ProjectId),
  		":merge_request_idd": string(mr.Iid),
  	})
  
  	encodedRequest, err := json.Marshal(mr)
  	if err != nil {
  		return err
  	}
  
  	data, _, err := g.buildAndExecRequest("PUT", u.String(), encodedRequest)
  	if err != nil {
  		return err
  	}
  
  	err = json.Unmarshal(data, mr)
  	if err != nil {
  		panic(err)
  	}
  
  	return nil
  }
docs: /*
  Updates an existing merge request.
  
      PUT /projects/:id/merge_request/:merge_request_id
  
  Parameters:
  
      id               The ID of a project
  
  */