trigger.py: Add -realm to swarming args. This should fix recent permissions changes. Bug: chromium:1231092 Change-Id: Ie9b39449c861f3ab774334c4d392d1700c638ea9 Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/3040565 Reviewed-by: Jamie Madill <jmadill@chromium.org> Reviewed-by: Andrii Shyshkalov <tandrii@google.com> Commit-Queue: Jamie Madill <jmadill@chromium.org>