Bump rack from 2.0.9 to 2.2.3

Bumps [rack](https://github.com/rack/rack) from 2.0.9 to 2.2.3.
- [Release notes](https://github.com/rack/rack/releases)
- [Changelog](https://github.com/rack/rack/blob/master/CHANGELOG.md)
- [Commits](rack/rack@2.0.9...2.2.3)

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

Gemfile.lock

@@ -25,12 +25,12 @@ GEM
     parallel (1.20.1)
     parser (3.0.0.0)
       ast (~> 2.4.1)
-    rack (2.0.9)
+    rack (2.2.3)
     rack-protection (2.1.0)
       rack
     rainbow (3.0.0)
     rake (13.0.3)
-    redis (4.2.5)
+    redis (4.1.4)
     regexp_parser (2.0.3)
     rexml (3.2.4)
     rspec (3.10.0)
@@ -66,11 +66,11 @@ GEM
       rubocop (~> 1.0)
       rubocop-ast (>= 1.1.0)
     ruby-progressbar (1.11.0)
-    sidekiq (5.2.8)
+    sidekiq (5.2.9)
       connection_pool (~> 2.2, >= 2.2.2)
-      rack (< 2.1.0)
+      rack (~> 2.0)
       rack-protection (>= 1.5.0)
-      redis (>= 3.3.5, < 5)
+      redis (>= 3.3.5, < 4.2)
     thread_safe (0.3.6)
     tzinfo (1.2.7)
       thread_safe (~> 0.1)