message: fix: remove erroneous env var
diff: {
  - "rewrites": [{ "source": "/(.*)", "destination": "/index.html" }],
  - "build": {
  - "env": {
  - "VERCEL_URL": "system"
  - }
  - }
  + "rewrites": [{ "source": "/(.*)", "destination": "/index.html" }]
  }
  