chore: fix webpack version syntax

package.json

@@ -94,7 +94,7 @@
     "underscore-template-loader": "^1.0.0",
     "webpack": "^4.25.0",
     "webpack-cli": "^3.0.8",
-    "webpack-dev-server": "3.1.14",
+    "webpack-dev-server": "^3.1.14",
     "webpack-merge": "^4.1.2",
     "webpack-visualizer-plugin": "^0.1.11"
   },