Bump astro from 6.4.2 to 6.4.8 in /docs (#1068)

Bumps [astro](https://github.com/withastro/astro/tree/HEAD/packages/astro) from 6.4.2 to 6.4.8.
- [Release notes](https://github.com/withastro/astro/releases)
- [Changelog](https://github.com/withastro/astro/blob/astro@6.4.8/packages/astro/CHANGELOG.md)
- [Commits](https://github.com/withastro/astro/commits/astro@6.4.8/packages/astro)

---
updated-dependencies:
- dependency-name: astro
  dependency-version: 6.4.8
  dependency-type: direct:production
...

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docs/package.json

@@ -19,7 +19,7 @@
     "@fontsource/ibm-plex-mono": "^5.2.7",
     "@fontsource/ibm-plex-sans": "^5.2.8",
     "@tailwindcss/vite": "^4.3.0",
-    "astro": "^6.4.2",
+    "astro": "^6.4.8",
     "sharp": "^0.34.5",
     "starlight-openapi": "^0.25.3",
     "svelte": "^5.56.0",