Suricata

As seen in https://github.com/OISF/suricata/pull/11443, many places of our documentation still refer
to legacy rule keywords (e.g., for http_host, cf: https://docs.suricata.io/en/latest/search.html?q=http_host&check_keywords=yes&area=default).

This ticket is an umbrella to track the efforts to update our user guide to use only the newer version of those keywords.