swap jquery 1 for jquery 3

_includes/head.html

@@ -7,7 +7,7 @@
   <link rel="shortcut icon" href="{{ "/favicon.ico" | relative_url }}">
   <link rel="stylesheet" href="{{ "/assets/slick/slick.css?ver=2018.11.23" | relative_url }}">
   <link rel="stylesheet" href="{{ "/assets/main.css?ver=2018.11.23" | relative_url }}">
-  <script src="https://code.jquery.com/jquery-1.12.4.min.js" integrity="sha256-ZosEbRLbNQzLpnKIkEdrPv7lOy9C27hHQ+Xp8a4MxAQ=" crossorigin="anonymous"></script>
+  <script src="https://code.jquery.com/jquery-3.3.1.min.js" integrity="sha256-FgpCb/KJQlLNfOu91ta32o/NMZxltwRo8QtmkMRdAu8=" crossorigin="anonymous"></script>
   {%- feed_meta -%}
   {%- if jekyll.environment == 'production' and site.google_analytics -%}
     {%- include google-analytics.html -%}