audio/beets: update 2.0.0 -> 2.5.1

Changelog: https://github.com/beetbox/beets/releases/tag/v2.5.1

Major changes:
Unbreak audio/beats. The breakage was due to an sqlite2
requirement, disabled in ports, to support Double-quoted String
Literals.

Also reorder sections and fix style to make portlint and portfmt
happy.

PR: 289098
Reported by: vishwin
Approved by: Leonhard Wachutka <leonhard@wachutka.eu> (maintainer)