Exclude the ASAN bot from the list of rebaseline bots.

The bot is not a source of truth for baselines and it slows down
rebaselines.

Review URL: https://codereview.chromium.org/290123002

git-svn-id: svn://svn.chromium.org/blink/trunk@174136 bbb929c8-8fbe-4397-9dbb-9b2b20218538