Skip es6/typedarray-copywithin for ignition

R=machenbach@chromium.org
BUG=v8:4961
NOTRY=true
LOG=N
NOTREECHECKS=true

Review-Url: https://codereview.chromium.org/1915033008
Cr-Commit-Position: refs/heads/master@{#35842}

test/mjsunit/mjsunit.status

@@ -768,6 +768,9 @@
   'es6/debug-liveedit-new-target-3': [FAIL],
   'es6/generators-debug-liveedit': [FAIL],
 
+  # TODO(yangguo, 4961): test failure with GC stress
+  'es6/typedarray-copywithin': [PASS, ['gc_stress', SKIP]],
+
   # TODO(mythria, 4780): Related to type feedback for calls in interpreter.
   'array-literal-feedback': [FAIL],
   'regress/regress-4121': [FAIL],