[tests] Increase stack-size limit to make tests pass in debug mode

This fixes webkit/run-json-stringify broken by
https://crrev.com/c/3222765

Failure: https://logs.chromium.org/logs/v8/buildbucket/cr-buildbucket/8832393633085738145/+/u/Bisect_23af060d/Retry_-_default/run-json-stringify


Bug: chromium:1244145
Change-Id: I1235f6db8ab10356476cd1028b20300f86510119
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3242005
Commit-Queue: Camillo Bruni <cbruni@chromium.org>
Auto-Submit: Camillo Bruni <cbruni@chromium.org>
Reviewed-by: Shu-yu Guo <syg@chromium.org>
Cr-Commit-Position: refs/heads/main@{#77533}

test/webkit/run-json-stringify.js

@@ -3,7 +3,7 @@
 // found in the LICENSE file.
 
 // This neuters too low stack size passed by the flag fuzzer.
-// Flags: --stack-size=864
+// Flags: --stack-size=1000
 
 var nativeJSON = this.JSON;
 this.JSON = null;