Fix fourslash test

Author: mhegazy

tests/cases/fourslash/referencesForIndexProperty2.ts

@@ -3,7 +3,8 @@
 // References to a unknown index property
 
 ////var a;
-////a[/**/"blah"];
+////a["[|blah|]"];
 
-goTo.marker("");
+goTo.position(test.ranges()[0].start, test.ranges()[0].fileName);
 verify.referencesAre(test.ranges());
+