[a11y] Calendar for accessibility task force meetings, from Aug 12 onwards

Dear all,

As per the decision made in the last accessibility task force meeting, our next meeting is scheduled on Thursday, August 12, 2021, at 14 UTC.
Attached is the calendar file for the month of August and September.
We have meetings on 2nd and 4th Thursday of the month.

With regards
Avneesh Singh