Revert of [debugger] unskip mjsunit/debug-stepin-builtin-callback-opt....

Revert of [debugger] unskip mjsunit/debug-stepin-builtin-callback-opt. (patchset #1 id:1 of https://codereview.chromium.org/1927543002/ )

Reason for revert:
Now we do have a repro!

https://build.chromium.org/p/client.v8/builders/V8%20Linux%20-%20gc%20stress/builds/3187/steps/Mjsunit%20-%20ignition%20-%20turbofan/logs/debug-stepin-builtin-..

Original issue's description:
> [debugger] unskip mjsunit/debug-stepin-builtin-callback-opt.
>
> This test does not seem to fail any longer.
>
> R=machenbach@chromium.org
> BUG=v8:4690
> LOG=N
>
> Committed: https://crrev.com/f8e44fb5aaaa80cf2d39bc3164f2c962a6b57f5e
> Cr-Commit-Position: refs/heads/master@{#35814}

TBR=machenbach@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=v8:4690

Review URL: https://codereview.chromium.org/1931433002

Cr-Commit-Position: refs/heads/master@{#35815}

test/mjsunit/mjsunit.status

@@ -751,6 +751,9 @@
 
 ##############################################################################
 ['ignition or ignition_turbofan', {
+  # TODO(yangguo,4690): flaky failures on the bots.
+  'debug-stepin-builtin-callback-opt': [SKIP],
+
    # TODO(rmcilroy,4765): assertion failures in LiveEdit tests.
   'debug-liveedit-restart-frame': [FAIL],
   'debug-liveedit-literals': [FAIL],