Replace to shakapacker from webpacker

config/webpack/webpack.config.js

@@ -0,0 +1,14 @@
+const { existsSync } = require('fs');
+const { resolve } = require('path');
+const { env } = require('shakapacker');
+const baseConfig = require('./environments/base');
+
+function getWebpackConfig() {
+  const { nodeEnv } = env;
+  const path = resolve(__dirname, 'environments', `${nodeEnv}.js`);
+  const enviromentConfig = existsSync(path) ? require(path) : baseConfig;
+
+  return enviromentConfig;
+}
+
+module.exports = getWebpackConfig();