fix: remove unnecessary return statement to comply with rubocop

Author: 2fa

lib/puppet/provider/firewall/firewall.rb

@@ -443,8 +443,6 @@ def insync?(context, _name, property_name, is_hash, should_hash)
         should = should.tr('-', ':') if ports.include?(property_name)
 
         is == should
-      else
-        return nil
       end
     when :string_hex
       # Compare the values with any whitespace removed