Use Commit#show instead of Commits#show to view a single commit

Commits#show (plural) is going to be for showing commit history on a
specific path.

app/roles/static_model.rb

@@ -25,6 +25,10 @@ module StaticModel
     id
   end
 
+  def new_record?
+    false
+  end
+
   def persisted?
     false
   end