Bump @astrojs/vercel from 9.0.4 to 10.0.3

Bumps [@astrojs/vercel](https://github.com/withastro/astro/tree/HEAD/packages/integrations/vercel) from 9.0.4 to 10.0.3.
- [Release notes](https://github.com/withastro/astro/releases)
- [Changelog](https://github.com/withastro/astro/blob/main/packages/integrations/vercel/CHANGELOG.md)
- [Commits](https://github.com/withastro/astro/commits/@astrojs/vercel@10.0.3/packages/integrations/vercel)

---
updated-dependencies:
- dependency-name: "@astrojs/vercel"
  dependency-version: 10.0.3
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

landing/package.json

@@ -12,7 +12,7 @@
   },
   "dependencies": {
     "@astrojs/mdx": "^5.0.2",
-    "@astrojs/vercel": "^9.0.4",
+    "@astrojs/vercel": "^10.0.3",
     "@polar-sh/astro": "^0.7.5",
     "astro": "^5.18.0",
     "shepherd.js": "workspace:*"