Bump rack from 2.2.3 to 2.2.8.1

Bumps [rack](https://github.com/rack/rack) from 2.2.3 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@2.2.3...v2.2.8.1)

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

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

Gemfile.lock

@@ -480,7 +480,7 @@ GEM
       coderay (~> 1.1)
       method_source (~> 1.0)
     public_suffix (4.0.5)
-    rack (2.2.3)
+    rack (2.2.8.1)
     rainbow (3.0.0)
     rake (13.0.1)
     regexp_parser (1.7.1)