Bump rack from 2.2.8 to 2.2.9 (#164)

Bumps [rack](https://github.com/rack/rack) from 2.2.8 to 2.2.9.
- [Release notes](https://github.com/rack/rack/releases)
- [Changelog](https://github.com/rack/rack/blob/main/CHANGELOG.md)
- [Commits](rack/rack@v2.2.8...v2.2.9)

---
updated-dependencies:
- dependency-name: rack
  dependency-type: indirect
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Gemfile.lock

@@ -218,7 +218,7 @@ GEM
       nio4r (~> 2.0)
     raabro (1.4.0)
     racc (1.7.3)
-    rack (2.2.8)
+    rack (2.2.9)
     rack-cors (2.0.1)
       rack (>= 2.0.0)
     rack-test (2.1.0)