x11/darkman: update to 1.5.0
No shell completions after https://gitlab.com/WhyNotHugo/darkman/-/fde9a24f3f1d
$ darkman completion zsh
darkman: No subcommand or positional value found at position 1.
Available subcommands: get set toggle run
Changes: https://gitlab.com/WhyNotHugo/darkman/-/compare/v1.4.0...v1.5.0