去掉实践课程的二维码

app/views/subjects/right_banner.json.jbuilder

@@ -1,4 +1,4 @@
-json.qrcode_img Util::FileManage.exists?(@subject, '_qrcode') ? Util::FileManage.source_disk_file_url(@subject, '_qrcode') : nil
+json.qrcode_img nil
 
 json.members @members do |member|
   json.partial! 'subject_member', locals: { user: member.user }