https://github.com/ruby/ipaddr/blob/master/lib/ipaddr.rb#L708 since e0feb0708bb4194dcebea1f8f47cde441af2dab5 uses Regexp#match?, which was added in Ruby 2.4, but `required_ruby_version` is `>= 2.3`.
https://github.com/ruby/ipaddr/blob/master/lib/ipaddr.rb#L708 since e0feb07 uses Regexp#match?, which was added in Ruby 2.4, but
required_ruby_versionis>= 2.3.