www/nginx: Add support for 3rd party stream-lua-nginx-module

PR: 277719
Approved by: maintainer timeout
Reported by: Eirik Oeverby <ltning-freebsd@anduin.net>
Sponsored by: Modirum MDPay
Sponsored by: Klara, Inc.
Co-authored-by: Xavier Beaudouin <kiwi@oav.net>

(cherry picked from commit edac05fd7cb3fa2f9c794165b8ffcfc9e32c20c4)