Bump rack from 2.2.6.4 to 2.2.8.1 in /website

Bumps [rack](https://github.com/rack/rack) from 2.2.6.4 to 2.2.8.1.
- [Release notes](https://github.com/rack/rack/releases)
- [Changelog](https://github.com/rack/rack/blob/main/CHANGELOG.md)
- [Commits](rack/rack@v2.2.6.4...v2.2.8.1)

---
updated-dependencies:
- dependency-name: rack
  dependency-type: direct:development
...

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

website/Gemfile.lock

@@ -11,7 +11,7 @@ GEM
     nio4r (2.7.0)
     puma (6.4.2)
       nio4r (~> 2.0)
-    rack (2.2.6.4)
+    rack (2.2.8.1)
     rack-protection (3.0.5)
       rack
     redis (4.1.3)