build(deps): bump the docs-dependencies group in /docs with 3 updates

Bumps the docs-dependencies group in /docs with 3 updates: [@astrojs/tailwind](https://github.com/withastro/astro/tree/HEAD/packages/integrations/tailwind), [astro](https://github.com/withastro/astro/tree/HEAD/packages/astro) and [tailwindcss](https://github.com/tailwindlabs/tailwindcss/tree/HEAD/packages/tailwindcss).


Updates `@astrojs/tailwind` from 5.1.4 to 5.1.5
- [Release notes](https://github.com/withastro/astro/releases)
- [Changelog](https://github.com/withastro/astro/blob/main/packages/integrations/tailwind/CHANGELOG.md)
- [Commits](https://github.com/withastro/astro/commits/@astrojs/[email protected]/packages/integrations/tailwind)

Updates `astro` from 5.1.7 to 5.1.9
- [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/[email protected]/packages/astro)

Updates `tailwindcss` from 3.4.17 to 4.0.0
- [Release notes](https://github.com/tailwindlabs/tailwindcss/releases)
- [Changelog](https://github.com/tailwindlabs/tailwindcss/blob/next/CHANGELOG.md)
- [Commits](https://github.com/tailwindlabs/tailwindcss/commits/v4.0.0/packages/tailwindcss)

---
updated-dependencies:
- dependency-name: "@astrojs/tailwind"
  dependency-type: direct:production
  update-type: version-update:semver-patch
  dependency-group: docs-dependencies
- dependency-name: astro
  dependency-type: direct:production
  update-type: version-update:semver-patch
  dependency-group: docs-dependencies
- dependency-name: tailwindcss
  dependency-type: direct:production
  update-type: version-update:semver-major
  dependency-group: docs-dependencies
...

Signed-off-by: dependabot[bot] <[email protected]>

docs/package.json

@@ -12,11 +12,11 @@
     "@astrojs/check": "^0.9.4",
     "@astrojs/starlight": "^0.31.1",
     "@astrojs/starlight-tailwind": "^3.0.0",
-    "@astrojs/tailwind": "^5.1.4",
+    "@astrojs/tailwind": "^5.1.5",
     "@fontsource-variable/inter": "^5.1.1",
-    "astro": "^5.1.7",
+    "astro": "^5.1.9",
     "sharp": "^0.33.5",
-    "tailwindcss": "^3.4.17",
+    "tailwindcss": "^4.0.0",
     "typescript": "^5.7.3"
   },
   "devDependencies": {