Add instant join in page with the meeting friendly ID

[scouillard]

People using blackboard cannot send a link to the bbb meeting to the blackboard from their laptop. So they have to go to GL on the blackboard and log in their account. But, on blackboards there are no external keyboard - the keyboard is broadcasted on the screen and all the students can see.

Describe the solution you'd like Add a page on Greenlight so that users can join/start a meeting when entering the friendly id.