multimedia/tenacity: Add port: Tenacity is an easy-to-use multi-track audio editor and recorder

Tenacity is an easy-to-use, privacy-friendly, FLOSS,
cross-platform multi-track audio editor.

WWW: https://tenacityaudio.org/

PR: 290531
Reported by: Martin Filla <freebsd@sysctl.cz> (new maintainer)