Bump rack from 2.0.7 to 2.2.4

Bumps [rack](https://github.com/rack/rack) from 2.0.7 to 2.2.4.
- [Release notes](https://github.com/rack/rack/releases)
- [Changelog](https://github.com/rack/rack/blob/main/CHANGELOG.md)
- [Commits](rack/rack@2.0.7...2.2.4)

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

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

Gemfile.lock

@@ -105,7 +105,7 @@ GEM
       rack (>= 1.2, < 3)
     psych (2.2.1)
     public_suffix (5.0.0)
-    rack (2.0.7)
+    rack (2.2.4)
     rack-test (0.6.3)
       rack (>= 1.0)
     rails (5.0.0.1)