Merge pull request #78 from alphagov/dependabot/bundler/rack-2.2.8.1

Bump rack from 2.2.8 to 2.2.8.1

Author: sengi

Gemfile.lock

@@ -5,7 +5,7 @@ GEM
     eventmachine (1.2.7)
     prometheus_exporter (2.0.8)
       webrick
-    rack (2.2.8)
+    rack (2.2.8.1)
     thin (1.8.2)
       daemons (~> 1.0, >= 1.0.9)
       eventmachine (~> 1.0, >= 1.0.4)