Update package.json (#101)

Author: willum070

package.json

@@ -4,7 +4,7 @@
   "description": "Samples for the Google Maps JavaScript API.",
   "scripts": {
     "build-all": "npm run generate-index && npm run clean && npm run build --workspaces",
-    "build-prod": "npm run generate-index && npm run clean && npm run build --workspaces && ./.git/hooks/post-build",
+    "build-prod": "npm run generate-index && npm run clean && npm run build --workspaces && ./.git/hooks/post-build.sh",
     "clean": "bash samples/clean.sh",
     "generate-index": "bash samples/generate-index.sh"
   },