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:	WhyNotHugo/darkman@v1.4.0...v1.5.0