Bump rubocop-rails from 2.3.2 to 2.4.0 (activeadmin#5947)

dependabot-preview[bot] · web-flow · commit 330911b3d301 · 2019-11-27T05:27:14.000Z
diff --git a/Gemfile.lock b/Gemfile.lock
@@ -347,7 +347,7 @@ GEM
       rainbow (>= 2.2.2, < 4.0)
       ruby-progressbar (~> 1.7)
       unicode-display_width (>= 1.4.0, < 1.7)
-    rubocop-rails (2.3.2)
+    rubocop-rails (2.4.0)
       rack (>= 1.1)
       rubocop (>= 0.72.0)
     rubocop-rspec (1.37.0)
