Remove "position: sticky" stickyfill polyfill

From the script's repository: https://github.com/wilddeer/stickyfill

> Stickyfill did a good job while the browsers were implementing position: sticky
> support. You can now safely use stickies without a polyfill, all modern browsers
> support them natively:
>
> https://caniuse.com/?search=position%3Asticky

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

_includes/body.html

@@ -92,7 +92,6 @@
     <script defer src="/js/menu.js"></script>
     <script src="/js/jquery.js"></script>
     <script src="/js/bootstrap.min.js"></script>
-    <script src="/js/stickyfill.min.js"></script>
     <script defer src="/js/metadata.js"></script>
     <script defer src="/js/docs.js"></script>
     <script defer src="/js/toc.js"></script>

_scss/_layout.scss

@@ -131,7 +131,6 @@ section.section {
 }
 
 .sidebar {
-    position: -webkit-sticky;
     position: sticky;
     top: 55px;
     overflow: auto;

js/docs.js

@@ -245,8 +245,6 @@ $(document).ready(function () {
 
 
 $(document).ready(function () {
-    $(".sidebar").Stickyfill();
-
     // Add smooth scrolling to all links
     $(".nav-sidebar ul li a").on("click", function (event) {