argyllcms: 1.8.3 -> 2.0.0

Semi-automatic update. These checks were done:

- built on NixOS
- ran `/nix/store/hh6cqaai79dsh200g3c581iaq52yi580-argyllcms-2.0.0/bin/synthcal help` got 0 exit code
- found 2.0.0 with grep in /nix/store/hh6cqaai79dsh200g3c581iaq52yi580-argyllcms-2.0.0
- found 2.0.0 in filename of file in /nix/store/hh6cqaai79dsh200g3c581iaq52yi580-argyllcms-2.0.0