Bump rack from 2.0.8 to 2.1.4

Bumps [rack](https://github.com/rack/rack) from 2.0.8 to 2.1.4.
- [Release notes](https://github.com/rack/rack/releases)
- [Changelog](https://github.com/rack/rack/blob/master/CHANGELOG.md)
- [Commits](rack/rack@2.0.8...2.1.4)

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

Author: dependabot[bot]

Gemfile

@@ -1,4 +1,4 @@
 source 'https://rubygems.org'
 
-gem "rack", "~> 2.0"
+gem "rack", "~> 2.1"
 gem "puma", "~> 3.12"

Gemfile.lock

@@ -2,14 +2,14 @@ GEM
   remote: https://rubygems.org/
   specs:
     puma (3.12.4)
-    rack (2.0.8)
+    rack (2.1.4)
 
 PLATFORMS
   ruby
 
 DEPENDENCIES
   puma (~> 3.12)
-  rack (~> 2.0)
+  rack (~> 2.1)
 
 BUNDLED WITH
    1.17.1