Change ensure-crash.js to only be run with the default test configura…

…tion.

https://bugs.webkit.org/show_bug.cgi?id=271830
rdar://125557693

Reviewed by Justin Michaud.

There is no value in running this test repeatedly for different configurations.  It's a test of
the test harness.  Hence, it either works, or it doesn't.

* JSTests/stress/ensure-crash.js:

Canonical link: https://commits.webkit.org/276796@main

JSTests/stress/ensure-crash.js

@@ -1,5 +1,6 @@
 //@ crashOK!
 //@ skip if $hostOS == "windows"
+//@ runDefault
 
 $vm.crash();