Fix source of flakiness in DevTools test

When PlzServiceWorker is enabled, the output of this
test gets sometimes reordered (as there is no fixed
ordering constraint for the last two messages). Since
we don't care about the order, this CL sorts the
particular messages, thereby deflaking the test.

Bug: chromium:1046784, chromium:1244038
Change-Id: I35cdec9c3d7b53e774140f342864f4957180ded2
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3123760


Commit-Queue: Sigurd Schneider <sigurds@chromium.org>
Reviewed-by: Tim van der Lippe <tvanderlippe@chromium.org>
Cr-Commit-Position: refs/heads/main@{#915930}