playerctl: 0.5.0 -> 0.6.0

Semi-automatic update generated by https://github.com/ryantm/nixpkgs-update tools.

This update was made based on information from https://repology.org/metapackage/playerctl/versions.

These checks were done:

- built on NixOS
- ran ‘/nix/store/p0qhcjwl78w4rwdqwkh7zzifpc2v60p3-playerctl-0.6.0/bin/playerctl -h’ got 0 exit code
- ran ‘/nix/store/p0qhcjwl78w4rwdqwkh7zzifpc2v60p3-playerctl-0.6.0/bin/playerctl --help’ got 0 exit code
- ran ‘/nix/store/p0qhcjwl78w4rwdqwkh7zzifpc2v60p3-playerctl-0.6.0/bin/playerctl -v’ and found version 0.6.0
- ran ‘/nix/store/p0qhcjwl78w4rwdqwkh7zzifpc2v60p3-playerctl-0.6.0/bin/playerctl --version’ and found version 0.6.0
- found 0.6.0 with grep in /nix/store/p0qhcjwl78w4rwdqwkh7zzifpc2v60p3-playerctl-0.6.0
- directory tree listing: https://gist.github.com/0d015359b346703f7434ab698e4ad496