Lint os/mac/formula

Library/Homebrew/extend/os/mac/formula.rb

@@ -12,8 +12,10 @@ class Formula
       args.each { |key, version| args[key] = OS::Mac::Version.from_symbol(version) }
 
       return false if args[:after] && OS::Mac.version < args[:after]
+
       return false if args[:before] && OS::Mac.version >= args[:before]
-      return true
+
+      true
     end
   end
 end