updated build script

Author: webmasterdevlin

chapter-15/package.json

@@ -84,7 +84,7 @@
   },
   "scripts": {
     "start": "react-scripts start",
-    "build": "react-scripts build",
+    "build": "CI= react-scripts build NODE_ENV=production",
     "test": "react-scripts test",
     "eject": "react-scripts eject",
     "test:generators": "ts-node --project=./internals/ts-node.tsconfig.json ./internals/testing/test-generators.ts",