JS: Add regression tests for declared globals

Author: asgerf

javascript/ql/test/query-tests/Security/CWE-079/DomBasedXss/jquery-declare-any.ts

@@ -0,0 +1,7 @@
+import 'dummy';
+
+declare var $: any;
+
+function t() {
+    $(window.name); // $ MISSING: Alert
+}

javascript/ql/test/query-tests/Security/CWE-079/DomBasedXss/jquery-declare-type.ts

@@ -0,0 +1,7 @@
+import 'dummy';
+
+declare var $: JQueryStatic;
+
+function t() {
+    $(window.name); // $ MISSING: Alert
+}