Bump rack from 2.2.20 to 2.2.22

Bumps [rack](https://github.com/rack/rack) from 2.2.20 to 2.2.22.
- [Release notes](https://github.com/rack/rack/releases)
- [Changelog](https://github.com/rack/rack/blob/main/CHANGELOG.md)
- [Commits](rack/rack@v2.2.20...v2.2.22)

---
updated-dependencies:
- dependency-name: rack
  dependency-version: 2.2.22
  dependency-type: direct:development
...

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

Author: dependabot[bot]

Gemfile.lock

@@ -10,7 +10,7 @@ GEM
       metaclass (~> 0.0.1)
     mustermann (2.0.2)
       ruby2_keywords (~> 0.0.1)
-    rack (2.2.20)
+    rack (2.2.22)
     rack-cors (1.0.5)
       rack (>= 1.6.0)
     rack-protection (2.2.3)