chore: add survey link

Author: rigor789

layouts/_partials/header.ejs

@@ -1,4 +1,9 @@
-
+<a href="https://www.surveymonkey.com/r/6FYQDZY?ref=nativescript-vue"
+   target="_blank"
+   rel="noopener"
+   class="block bg-blue-light md:bg-green md:border-t-8 border-green p-4 md:p-0 text-center no-underline text-white">
+   Help us improve NativeScript by filling out a quick survey!
+</a>
 <!--
 <a href="https://www.youtube.com/watch?v=QvU3eYova6I"
    target="_blank"