chore: add prism-ruby

Author: maolonglong

index.html

@@ -107,6 +107,7 @@
   <script src="//cdn.jsdelivr.net/npm/prismjs/components/prism-python.min.js"></script>
   <script src="//cdn.jsdelivr.net/npm/prismjs/components/prism-swift.min.js"></script>
   <script src="//cdn.jsdelivr.net/npm/prismjs/components/prism-nim.min.js"></script>
+  <script src="//cdn.jsdelivr.net/npm/prismjs/components/prism-ruby.min.js"></script>
   <script src="//cdn.jsdelivr.net/npm/docsify-copy-code@2.1.1/dist/docsify-copy-code.min.js"></script>
   <script src="//cdn.jsdelivr.net/npm/docsify/lib/plugins/search.min.js"></script>
   <script src="//cdn.jsdelivr.net/npm/docsify/lib/plugins/emoji.min.js"></script>