chore(build): try to build demo and docs (#3434)

extensions/cornerstone-dicom-rt/.webpack/webpack.dev.js

@@ -1,8 +1,12 @@
 const path = require('path');
-const webpackCommon = require('./../../../.webpack/webpack.commonjs.js');
+const webpackCommon = require('./../../../.webpack/webpack.base.js');
 const SRC_DIR = path.join(__dirname, '../src');
 const DIST_DIR = path.join(__dirname, '../dist');
 
-module.exports = (env, argv) => {
-  return webpackCommon(env, argv, { SRC_DIR, DIST_DIR });
+const ENTRY = {
+  app: `${SRC_DIR}/index.tsx`,
+};
+
+module.exports = (env, argv) => {
+  return webpackCommon(env, argv, { SRC_DIR, DIST_DIR, ENTRY });
 };