test_push: add link to monarch stats on success fraction

BUG=None
TEST=None

Change-Id: Icc85f287144cd34b15ac433e3db67d47ef2c0ab5
Reviewed-on: https://chromium-review.googlesource.com/565071
Commit-Ready: Aviv Keshet <akeshet@chromium.org>
Tested-by: Aviv Keshet <akeshet@chromium.org>
Reviewed-by: Xixuan Wu <xixuan@chromium.org>
diff --git a/site_utils/test_push.py b/site_utils/test_push.py
index 57a14dc..af579fb 100755
--- a/site_utils/test_push.py
+++ b/site_utils/test_push.py
@@ -659,7 +659,9 @@
                      'repos and the corresponding test HEAD.\n\n%s\n\n.'
                      'Error occurred during test:\n\n%s\n\n'
                      'All logs have been saved to '
-                     '/var/log/test_push/test_push.log on push master. Detail '
+                     '/var/log/test_push/test_push.log on push master. '
+                     'Stats on recent success rate can be found at '
+                     'go/test-push-stats . Detailed '
                      'debugging info can be found at go/push-to-prod' %
                      (updated_repo_msg, str(e)) + '\n'.join(run_suite_output)))
         raise