Update dependency @astrojs/tailwind to v6

Author: renovate[bot]

package-lock.json

@@ -15,7 +15,7 @@
     "@astrojs/netlify": "^6.0.1",
     "@astrojs/react": "^4.1.2",
     "@astrojs/sitemap": "^3.2.1",
-    "@astrojs/tailwind": "^5.1.4",
+    "@astrojs/tailwind": "^6.0.0",
     "@netlify/functions": "^3.0.0",
     "@types/react": "^18.3.12",
     "@types/react-dom": "^18.3.1",