Revert "Mark json-parser-recursive as slow"

This reverts commit 71e27849.

Reason for revert: As of https://crrev.com/c/3059685 it's fast.

Original change's description:
> Mark json-parser-recursive as slow
>
> Bug: v8:12029
> Change-Id: I0d25f8c844c9826e10ca2ccc6beb385439e97dde
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3058451
> Reviewed-by: Clemens Backes <clemensb@chromium.org>
> Commit-Queue: Zhi An Ng <zhin@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#75968}

Bug: v8:12029
Change-Id: I9536adbe4d8434e44d3e113104694baa3b3cea47
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3059687
Auto-Submit: Leszek Swirski <leszeks@chromium.org>
Commit-Queue: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Cr-Commit-Position: refs/heads/master@{#75977}

test/mjsunit/mjsunit.status

@@ -78,9 +78,6 @@
   # https://crbug.com/v8/10948
   'wasm/atomics': [PASS, ['arch == arm and not simulator_run', SKIP]],
 
-  # https://crbug.com/v8/12029
-  'json-parser-recursive': [PASS, SLOW],
-
   ##############################################################################
   # Tests where variants make no sense.
   'd8/enable-tracing': [PASS, NO_VARIANTS],