Bump @astrojs/sitemap from 3.6.1 to 3.7.0

Bump @astrojs/sitemap from 3.6.1 to 3.7.0

Bumps [@astrojs/sitemap](https://github.com/withastro/astro/tree/HEAD/packages/integrations/sitemap) from 3.6.1 to 3.7.0.
- [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@3.7.0/packages/integrations/sitemap)

---
updated-dependencies:
- dependency-name: "@astrojs/sitemap"
  dependency-version: 3.7.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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