Bug 1870931 - Mark non262/TypedArray/large-arrays.js as slow r=iain

Takes 45s locally for --jitflags=jstests

Depends on D196917

Differential Revision: https://phabricator.services.mozilla.com/D196918

js/src/tests/non262/TypedArray/large-arrays.js

@@ -1,4 +1,4 @@
-// |reftest| skip-if(!xulRuntime.shell)
+// |reftest| slow skip-if(!xulRuntime.shell)
 
 // Test that we can access TypedArrays beyond the 4GB mark, if large buffers are
 // supported.