Update devtool

Author: gopinav

webpack/webpack.dev.js

@@ -1,4 +1,4 @@
 module.exports = {
   mode: 'development',
-  devtool: 'inline-source-map',
+  devtool: 'cheap-module-source-map',
 }

webpack/webpack.prod.js

@@ -1,4 +1,4 @@
 module.exports = {
   mode: 'production',
-  devtool: 'source-map'
+  devtool: 'source-map',
 }