Merge pull request #73 from travis-ci/dependabot/bundler/rack-2.2.3

Bump rack from 2.0.8 to 2.2.3

Author: DamianSzymanski

Gemfile.lock

@@ -52,7 +52,7 @@ GEM
       method_source (~> 0.9.0)
     puma (4.3.9)
       nio4r (~> 2.0)
-    rack (2.0.8)
+    rack (2.2.3)
     rack-protection (2.0.3)
       rack
     rack-test (1.0.0)