Fix bug where invalid room name in pass onto Jitsi (#75)

* Room name might be `Tom's Desk` which will try to GET https://meet.zinc.coop/Tom's%20Desk
which isn't a valid room.
* We should always use slug

convene-web/app/views/rooms/show.html.erb

@@ -3,7 +3,7 @@
   data-controller="video-room"
   data-target="video-room.wrapper"
   data-video-room-video-host="<%= current_workspace.jitsi_meet_domain %>"
-  data-video-room-name="<%= @current_room.name %>"
+  data-video-room-name="<%= @current_room.slug %>"
   class="bg-gray-800"
 >
 </div>