Don't filter out MSAA events for the currently focused object, even if the winEvent limit has been exceeded for that thread (#11520)
* IAccessibleHandler: Still allow processing of winEvents for the currently focused object, even if the winEvent limit has been exceeded for that thread.
* IAccessibleHandler.OrderedWinEventLimitor.flushEvents: alwaysAllowedObjects is now optional.
* OrderedWinEventLimitor.flushEvents: counts of events per thread should still go up if the event is for the focus, even though we won't drop the event if we are over the limit.
* IAccessibleHandler: add typing information to OrderedWinEventLimitor.flushEvents and improve logic readability around skipping events due to exceeded count per thread.
* Tests for limit of events per thread
* OrderedWinEventLimiter: fix off-by-one error: 10 events per thread is emitted now, not 11.
* OrderedWinEventLimiter unit tests: remove work-arounds for off-by-one error for events per thread, and no longer expect certain failures
* Fix linting issue
* Update what's new
Co-authored-by: Reef Turner <reef@nvaccess.org>