Bug 1491326 - Fix typo in test code r=me on a CLOSED TREE

js/src/jit-test/tests/gc/bug-1491326.js

@@ -1,6 +1,6 @@
 // |jit-test| --fuzzing-safe
 
-if (!('oomTest') in this)
+if (!('oomTest' in this))
     quit();
 
 var g = newGlobal();