dev(yarn link): make it possible to yarn link easily with cornerstone3D and update docs (#3563)

platform/app/.webpack/webpack.pwa.js

@@ -186,8 +186,6 @@ module.exports = (env, argv) => {
         chunkFilename: '[id].css',
       })
     );
-  } else {
-    mergedConfig.plugins.push(new webpack.HotModuleReplacementPlugin());
   }
 
   return mergedConfig;