add an npm script for webpack-dev-server

Author: nicoqh

package.json

@@ -1,7 +1,8 @@
 {
   "scripts": {
     "build": "webpack --env environment=production --config webpack.config.js",
-    "dev": "webpack --env environment=development --config webpack.config.js"
+    "dev": "webpack --env environment=development --config webpack.config.js",
+    "devserver": "webpack-dev-server --env environment=development --config webpack.config.js"
   },
   "devDependencies": {
     "@babel/cli": "^7.17.6",