Mark json-parser-recursive as slow

Bug: v8:12029
Change-Id: I0d25f8c844c9826e10ca2ccc6beb385439e97dde
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3058451Reviewed-by: Clemens Backes <clemensb@chromium.org>
Commit-Queue: Zhi An Ng <zhin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#75968}

test/mjsunit/mjsunit.status

@@ -78,6 +78,9 @@
   # 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],