mopidy-iris: 3.12.4 -> 3.13.0

Semi-automatic update. These checks were performed:

- built on NixOS
- found 3.13.0 with grep in /nix/store/c2jcl71cqfd0a48mmn9g2sg2wzk8f47x-mopidy-iris-3.13.0
- found 3.13.0 in filename of file in /nix/store/c2jcl71cqfd0a48mmn9g2sg2wzk8f47x-mopidy-iris-3.13.0

cc "@rvolosatovs"