Add linux-presubmit to the CQ.

This will run the PRESUBMIT.py scripts in the repo as part of the CQ run
to prevent changes from landing that break the presubmit checks.

Bug: 407065680
Change-Id: Idaf6e2f5512044fc0ebd93be4fd32753a4256bc6
Reviewed-on: https://chromium-review.googlesource.com/c/infra/chromium/+/6513271
Reviewed-by: Struan Shrimpton <sshrimp@google.com>
Commit-Queue: Struan Shrimpton <sshrimp@google.com>
Auto-Submit: Garrett Beaty <gbeaty@google.com>