Added test case which is not detected by dataflow.

javascript/ql/test/library-tests/frameworks/ClientRequests/superagent.js

@@ -0,0 +1,7 @@
+import { superagent } from "./superagentWrapper.js";
+
+function test(url) {
+    superagent('GET', url); // Not flagged
+    superagent.del(url); // Not flagged
+    superagent.agent().post(url).send(data); // Not flagged
+}

javascript/ql/test/library-tests/frameworks/ClientRequests/superagentWrapper.js

@@ -0,0 +1,2 @@
+import superagent from 'superagent';
+export { superagent }