[PRQ#59931] Deletion Request for mixxx_beta-git

MarsSeed [1] filed a deletion request for mixxx_beta-git [2]: Upstream no longer has beta branches. Only the 'main' development branch, and past release maintenance branches like '2.4'. [a] Arch repo offers the stable mixxx pkg (v2.4.0 atm), and AUR has a mixxx-git build for the devel version. [a]: https://github.com/mixxxdj/mixxx/branches [1] https://aur.archlinux.org/account/MarsSeed/ [2] https://aur.archlinux.org/pkgbase/mixxx_beta-git/