multimedia/tautulli: Update to 2.7.7

While here switch to DISTVERSION, pet portclippy and portfmt.

Changes: https://github.com/Tautulli/Tautulli/releases/tag/v2.7.7
PR: 259479
Approved by: portmgr (maintainer timeout), philip (mentor)
Differential Revision: https://reviews.freebsd.org/D33336