[Sheriff] Fix TestExpectations test disabling

Two changes:
 - These tests are flaky, so their expectations should include "pass"
 - The JS one is failing due to a timeout, not a failure

Bug: 1393067, 1393056
Change-Id: I790ef47092d8bbcedcf2657d65903bb3916931d2
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4053400


Auto-Submit: thefrog <thefrog@chromium.org>
Commit-Queue: thefrog <thefrog@chromium.org>
Reviewed-by: Michael Wilson <mjwilson@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1075372}