Have wasm/demo's "test" npm script build the demo in release mode

Author: coolreader18

wasm/demo/package.json

@@ -24,7 +24,7 @@
         "dev": "webpack-dev-server -d",
         "build": "webpack",
         "dist": "webpack --mode production",
-        "test": "webpack && cd ../tests && pipenv run pytest"
+        "test": "webpack --mode production && cd ../tests && pipenv run pytest"
     },
     "repository": {
         "type": "git",