competition: fix form valid bug

app/forms/competitions/save_team_form.rb

@@ -73,10 +73,10 @@ class Competitions::SaveTeamForm
 
   # 竞赛是否限制了职业
   def check_creator_identity_enrollable
-    if user.is_teacher? && competition.teacher_enroll_forbidden?
+    if creator.is_teacher? && competition.teacher_enroll_forbidden?
       errors.add(:creator, :teacher_enroll_forbidden)
       return false
-    elsif !user.is_teacher? && competition.member_enroll_forbidden?
+    elsif !creator.is_teacher? && competition.member_enroll_forbidden?
       errors.add(:creator, :member_enroll_forbidden)
       return false
     end
@@ -86,9 +86,9 @@ class Competitions::SaveTeamForm
 
   # 创建者是否能多次报名
   def check_creator_multiple_enrollable
-    return unless competition.enrolled?(user)
+    return unless competition.enrolled?(creator)
 
-    if (user.is_teacher? && competition.teacher_multiple_limited?) || (!user.is_teacher? && competition.member_multiple_limited?)
+    if (creator.is_teacher? && competition.teacher_multiple_limited?) || (!creator.is_teacher? && competition.member_multiple_limited?)
       errors.add(:creator, :enrolled)
       return false
     end