Do not run mjsunit/compare-known-objects-slow in GC-stress mode.

test/mjsunit/mjsunit.status

 # Copyright 2012 the V8 project authors. All rights reserved.
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
 #
 #     * Redistributions of source code must retain the above copyright
 #       notice, this list of conditions and the following disclaimer.
 #     * Redistributions in binary form must reproduce the above
 #       copyright notice, this list of conditions and the following
 #       disclaimer in the documentation and/or other materials provided
@@ skipping 281 matching lines @@
   'fast-prototype': [SKIP],
   'field-type-tracking': [SKIP],
   'getters-on-elements': [SKIP],
   'es6/block-let-crankshaft': [SKIP],
   'opt-elements-kind': [SKIP],
   'osr-elements-kind': [SKIP],
   'regress/regress-crbug-137689': [SKIP],
   'regress/regress-165637': [SKIP],
   'regress/regress-2249': [SKIP],
   'regress/regress-4121': [SKIP],
+  'compare-known-objects-slow': [SKIP],
   # Tests taking too long
   'debug-stepout-scope-part8': [SKIP],
   'mirror-object': [SKIP],
   'packed-elements': [SKIP],
   'regress/regress-1122': [SKIP],
   'regress/regress-331444': [SKIP],
   'regress/regress-353551': [SKIP],
   'regress/regress-crbug-119926': [SKIP],
   'regress/short-circuit': [SKIP],
   'stack-traces-overflow': [SKIP],
@@ skipping 397 matching lines @@
   'd8-worker-sharedarraybuffer': [SKIP],
 }],  # 'predictable == True'
 
 ##############################################################################
 ['arch == ppc and simulator_run == True or arch == ppc64 and simulator_run == True', {
 
   # take too long with the simulator.
   'regress/regress-1132': [SKIP],
 }],  # 'arch == ppc and simulator_run == True'
 ]