add build:ui-demo script

Author: neSpecc

package.json

@@ -7,6 +7,7 @@
     "dev": "vite",
     "build": "yarn build:ui && vue-tsc && vite build",
     "build:ui": "yarn workspace @codexteam/ui run build",
+    "build:ui-demo": "yarn workspace @codexteam/ui-demo run build",
     "preview": "vite preview",
     "lint": "eslint",
     "lint:fix": "yarn lint --fix",