Bump astro from 3.6.5 to 5.15.9

Bumps [astro](https://github.com/withastro/astro/tree/HEAD/packages/astro) from 3.6.5 to 5.15.9.
- [Release notes](https://github.com/withastro/astro/releases)
- [Changelog](https://github.com/withastro/astro/blob/main/packages/astro/CHANGELOG.md)
- [Commits](https://github.com/withastro/astro/commits/astro@5.15.9/packages/astro)

---
updated-dependencies:
- dependency-name: astro
  dependency-version: 5.15.9
  dependency-type: direct:production
...

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

Author: dependabot[bot]

package.json

@@ -60,7 +60,7 @@
     "@octokit/plugin-retry": "^6.0.0",
     "@octokit/plugin-throttling": "^8.0.0",
     "@preact/signals": "^1.3.0",
-    "astro": "^3.6.5",
+    "astro": "^5.15.9",
     "clsx": "^2.1.1",
     "cross-fetch": "^4.1.0",
     "lodash-es": "^4.17.21",