Corrected linting issue in Turkish translation

src/js/select2/i18n/tr.js

@@ -2,7 +2,7 @@ define(function () {
   // Turkish
   return {
     errorLoading: function (){
-      return "Sonuç yüklenemedi";
+      return 'Sonuç yüklenemedi';
     },
     inputTooLong: function (args) {
       var overChars = args.input.length - args.maximum;