add umami tracker

Author: Gabriel-p

_layouts/default.html

@@ -5,7 +5,9 @@
     <meta http-equiv="X-UA-Compatible" content="IE=edge">
     <meta name="viewport" content="width=device-width, initial-scale=1">
 
-{% seo %}
+    <script defer src="https://cloud.umami.is/script.js" data-website-id="ba1fec27-d9e0-4e68-8d3c-bba77043c5bb"></script>
+
+    {% seo %}
     <link rel="stylesheet" href="{{ "/assets/css/style.css?v=" | append: site.github.build_revision | relative_url }}">
     <!--[if lt IE 9]>
     <script src="https://cdnjs.cloudflare.com/ajax/libs/html5shiv/3.7.3/html5shiv.min.js"></script>