fix(playground): use className instead of class (#2522)

Author: liamdebeasi

src/components/global/Playground/icons/IconDots.tsx

@@ -3,7 +3,7 @@ import React from 'react';
 import './IconDots.css';
 
 export const IconDots = () => (
-  <div class="icon__dots">
+  <div className="icon__dots">
     <svg viewBox="0 0 64 64">
       <circle transform="translate(32,32)" r="6"></circle>
     </svg>