[dev][keystone] Office hours revamp

Hi team, One of the outcomes of the PTG was to make more productive use of office hours by designating a topic ahead of time and working through it as a team. I've proposed to officially add the office hour to eavesdrop[1] and started a topic etherpad[2]. This week we'll finish the liaison review if it's not already completed during the meeting, and we'll do some bug triage. We should be sure to continuously reflect on how this is going and whether we should change our process or reschedule the session. Colleen [1] https://review.opendev.org/658909 [2] https://etherpad.openstack.org/p/keystone-office-hours-topics