fix competition enroll api

app/services/competitions/save_team_service.rb

@@ -32,7 +32,7 @@ class Competitions::SaveTeamService < ApplicationService
   private
 
   def update_teacher_team_members!
-    teacher_ids = Array.wrap(params[:teacher_ids]).map(:to_i)
+    teacher_ids = Array.wrap(params[:teacher_ids]).map(&:to_i)
     old_teacher_ids = team.team_members.where(role: 3).pluck(:user_id)
 
     destroy_teacher_ids = old_teacher_ids - teacher_ids
@@ -49,7 +49,7 @@ class Competitions::SaveTeamService < ApplicationService
   end
 
   def update_member_team_members!
-    member_ids = Array.wrap(params[:member_ids]).map(:to_i)
+    member_ids = Array.wrap(params[:member_ids]).map(&:to_i)
     old_member_ids = team.team_members.where(role: 2).pluck(:user_id)
 
     destroy_member_ids = old_member_ids - member_ids