Bump rack from 2.0.6 to 2.1.4 (#8)

Bumps [rack](https://github.com/rack/rack) from 2.0.6 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@2.0.6...2.1.4)

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

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

Author: dependabot[bot]

Gemfile

@@ -4,7 +4,7 @@ source 'https://rubygems.org'
 
 ruby '2.6.2'
 
-gem 'rack', '~> 2.0'
+gem 'rack', '~> 2.1'
 gem 'grape', '~> 1.2'
 gem 'grape-entity', '~> 0.7'
 gem 'pg', '~> 1.1'

Gemfile.lock

@@ -118,7 +118,7 @@ GEM
       byebug (~> 11.0)
       pry (~> 0.10)
     raabro (1.1.6)
-    rack (2.0.6)
+    rack (2.1.4)
     rack-accept (0.4.5)
       rack (>= 0.4)
     rack-ecg (0.0.5)
@@ -215,7 +215,7 @@ DEPENDENCIES
   paper_trail (~> 10.2.1)
   pg (~> 1.1)
   pry-byebug
-  rack (~> 2.0)
+  rack (~> 2.1)
   rack-ecg (~> 0.0.5)
   rack-test
   rake