fixed build error

Author: Ayush Kumar Mishra

examples/weather_report/package.json

@@ -9,7 +9,7 @@
   },
   "devDependencies": {
     "@wasm-tool/wasm-pack-plugin": "^1.1.0",
-    "copy-webpack-plugin": "^5.0.3",
+    "copy-webpack-plugin": "6.0.2",
     "webpack": "^4.42.0",
     "webpack-cli": "^3.3.3",
     "webpack-dev-server": "^3.7.1",