regex style change to make rubocop happy

Author: tskirvin

lib/puppet/provider/firewall/iptables.rb

@@ -576,7 +576,7 @@ def self.rule_to_hash(line, table, counter)
     end
 
     # manually remove comments if they made it this far
-    if values =~ %r{-m comment --comment}
+    if %r{-m comment --comment}.match?(values)
       values = values.sub(%r{-m comment --comment "((?:\\"|[^"])*)"}, {})
     end