npm: bump @astrojs/sitemap from 3.5.0 to 3.6.0

Bumps [@astrojs/sitemap](https://github.com/withastro/astro/tree/HEAD/packages/integrations/sitemap) from 3.5.0 to 3.6.0.
- [Release notes](https://github.com/withastro/astro/releases)
- [Changelog](https://github.com/withastro/astro/blob/main/packages/integrations/sitemap/CHANGELOG.md)
- [Commits](https://github.com/withastro/astro/commits/@astrojs/sitemap@3.6.0/packages/integrations/sitemap)

---
updated-dependencies:
- dependency-name: "@astrojs/sitemap"
  dependency-version: 3.6.0
  dependency-type: direct:development
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

package.json

@@ -53,7 +53,7 @@
         "@astrojs/alpinejs": "^0.4.8",
         "@astrojs/check": "^0.9.4",
         "@astrojs/mdx": "^4.3.4",
-        "@astrojs/sitemap": "^3.5.0",
+        "@astrojs/sitemap": "^3.6.0",
         "@tailwindcss/vite": "^4.1.12",
         "@types/alpinejs": "^3.13.11",
         "astro": "^5.13.2",