Update js_files.html

Author: talbring

_includes/js_files.html

@@ -4,5 +4,6 @@
 <script src="//code.jquery.com/jquery-1.10.2.min.js"></script>
 <script src="{{ "/js/bootstrap.min.js" | prepend: site.baseurl }} "></script>
 <script src="{{ "/js/typeahead.bundle.min.js" | prepend: site.baseurl }} "></script>
+<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.4.0/jquery.min.js"></script>
 
 <script src="{{ "/js/main.js" | prepend: site.baseurl }} "></script>