[autotest] Include bugs filed in run_suite output.

When tests run through a suite fail, we attempt to
file bugs. This change records the bug id in a keyval
which is then parsed by run suite to log a link to the
bug filed.

TEST=ran a failing suite and noted the links generated.
BUG=chromium:217209

Change-Id: If8b48cb16ad8f1fb3c71283266c14299f4521770
Reviewed-on: https://gerrit.chromium.org/gerrit/49472
Tested-by: Prashanth Balasubramanian <beeps@chromium.org>
Commit-Queue: Prashanth Balasubramanian <beeps@chromium.org>
Reviewed-by: Prashanth Balasubramanian <beeps@chromium.org>
diff --git a/server/cros/dynamic_suite/constants.py b/server/cros/dynamic_suite/constants.py
index b1e94c1..c980210 100644
--- a/server/cros/dynamic_suite/constants.py
+++ b/server/cros/dynamic_suite/constants.py
@@ -13,6 +13,7 @@
 JOB_REPO_URL = 'job_repo_url'
 VERSION_PREFIX = 'cros-version:'
 BOARD_PREFIX = 'board:'
+BUG_KEYVAL = '-Bug_Id'
 
 # Timings
 ARTIFACT_FINISHED_TIME = 'artifact_finished_time'