BBB Custom Completion Fixes

Note: this test requires that the Moodle is visible from outside and that the Bigbluebutton server is setup to enable analytics events. This test is also covered by phpunit and behat test. For the tests to work, the mock server should have been updated (and https://github.com/moodlehq/bigbluebutton_mock/pull/23 merged) Testing the completion Make sure that in Admin > Plugins > Bigbluebutton > Experimental Settings : Register live sessions is checked (bigbluebuttonbn_meetingevents_enabled) Create a course with completion tracking and enrol a student Create a Big Blue Button activity in the course and set completion tracking to "show activity as complete when conditions are met" and check the "Chats" and "Require raise hand" condition. Login as a student in that course Make the student join the meeting Raise hand Add a message in the chat Exit the meeting Check that on the BBB server the meeting event is sent (if not force it by going into /usr/local/bigbluebutton/core/scripts and running post_events/post_events_analytics_callback.rb  -m <meetingid>, from the list in /var/bigbluebutton/events/). Run the cron Refresh the page. Ensure that BBB activity is marked as completed for the given criteria (chat and raise hand)in main content AND in courseindex areas