vm_test_stages: Increase timeout for GCETest.

As the test suite of GCETest grows(in lakitu board), 60 minutes is not
enough to run them all. Increase the timeout to 90 minutes to get the
builder back. Will investigate further for increasing performance.

BUG=b:78306929
TEST=tryjob

Change-Id: Ib5deec4fde9fc9530aebf94df9465313ccb56aaf
Reviewed-on: https://chromium-review.googlesource.com/950317
Commit-Ready: Xuewei Zhang <xueweiz@google.com>
Tested-by: Xuewei Zhang <xueweiz@google.com>
Reviewed-by: Don Garrett <dgarrett@chromium.org>
Reviewed-by: Ningning Xia <nxia@chromium.org>
(cherry picked from commit 6388e725e46fd1d003f3ee851695ba0049196ddf)
Reviewed-on: https://chromium-review.googlesource.com/1019681
Reviewed-by: Daniel Wang <wonderfly@google.com>
Reviewed-by: Xuewei Zhang <xueweiz@google.com>
Tested-by: Robert Kolchmeyer <rkolchmeyer@google.com>
Commit-Queue: Robert Kolchmeyer <rkolchmeyer@google.com>
diff --git a/cbuildbot/stages/vm_test_stages.py b/cbuildbot/stages/vm_test_stages.py
index 6711138..6fde83d 100644
--- a/cbuildbot/stages/vm_test_stages.py
+++ b/cbuildbot/stages/vm_test_stages.py
@@ -298,8 +298,7 @@
 
   config_name = 'gce_tests'
 
-  # TODO: We should revisit whether GCE tests should have their own configs.
-  TEST_TIMEOUT = 60 * 60
+  TEST_TIMEOUT = 90 * 60
 
   def __init__(self, builder_run, board, gce_tests=None, **kwargs):
     """Initiailization of the VMTestStage.