Enable HWTest phase for monroe and panther paladin builders.
Enable HWTest phase for monroe and panther paladin builders.

As of a recent change, the lab will now return a warning if a
request is made to run HWTest for boards that don't exist.
This is done so that builders can request HWTest without regard
to whether hardware is available, so that the builders don't have
to track the inventory in the lab.

This chnage enables HWTest for the monroe and panther paladins,
as a first step to a new "run HWTest by default" behavior.  These
are the only paladins that currently disable HWTest.

BUG=chromium:353541
TEST=python cbuildbot_config_unittest.py

Change-Id: Iccfa19076a171f43a2b888558eea4d367f28e18f
Reviewed-on: https://chromium-review.googlesource.com/193653
Tested-by: Richard Barnette <9e7d66387742bf40b0d2548ef2b93e7c522ca0eb@chromium.org>
Reviewed-by: David James <f231dc574bbeb62604660cbc162d1b8642a0a3af@chromium.org>
Commit-Queue: Richard Barnette <9e7d66387742bf40b0d2548ef2b93e7c522ca0eb@chromium.org>

bpsinc-native/src_third_party_chromite,bpsinc-native/src_third_party_chromite,chadversary/chromiumos.chromite,bpsinc-native/src_third_party_chromite,chadversary/chromiumos.chromite