Bump rack from 2.2.3.1 to 2.2.4 (#18768)

Bumps [rack](https://github.com/rack/rack) from 2.2.3.1 to 2.2.4.
- [Release notes](https://github.com/rack/rack/releases)
- [Changelog](https://github.com/rack/rack/blob/main/CHANGELOG.md)
- [Commits](https://github.com/rack/rack/compare/2.2.3.1...2.2.4)

---
updated-dependencies:
- dependency-name: rack
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

Gemfile

@@ -10,7 +10,7 @@ gem 'puma', '~> 5.6'
 gem 'rails', '~> 6.1.6'
 gem 'sprockets', '~> 3.7.2'
 gem 'thor', '~> 1.2'
-gem 'rack', '~> 2.2.3'
+gem 'rack', '~> 2.2.4'
 
 gem 'hamlit-rails', '~> 0.2'
 gem 'pg', '~> 1.4'