Bump rack from 3.0.9 to 3.1.20

Bumps [rack](https://github.com/rack/rack) from 3.0.9 to 3.1.20.
- [Release notes](https://github.com/rack/rack/releases)
- [Changelog](https://github.com/rack/rack/blob/main/CHANGELOG.md)
- [Commits](rack/rack@v3.0.9...v3.1.20)

---
updated-dependencies:
- dependency-name: rack
  dependency-version: 3.1.20
  dependency-type: indirect
...

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

Author: dependabot[bot]

Gemfile.lock

@@ -504,7 +504,7 @@ GEM
     puma (6.4.2)
       nio4r (~> 2.0)
     racc (1.7.3)
-    rack (3.0.9)
+    rack (3.1.20)
     rackup (2.1.0)
       rack (>= 3)
       webrick (~> 1.8)