generate new test that did already exist & update all module snippets with declaration

test/httpGet/httpGet.js

@@ -0,0 +1,7 @@
+module.exports = httpGet = (url, callback, err = console.error) => {
+const request = new XMLHttpRequest();
+request.open('GET', url, true);
+request.onload = () => callback(request.responseText);
+request.onerror = () => err(request);
+request.send();
+};