yaws: 2.0 -> 2.0.4

Semi-automatic update. These checks were performed:

- built on NixOS
- ran `/nix/store/946hqpkgmb964ilf2sbk9ln4kfy7jnkr-yaws-2.0.4/bin/yaws -v` and found version 2.0.4
- ran `/nix/store/946hqpkgmb964ilf2sbk9ln4kfy7jnkr-yaws-2.0.4/bin/yaws --version` and found version 2.0.4
- found 2.0.4 with grep in /nix/store/946hqpkgmb964ilf2sbk9ln4kfy7jnkr-yaws-2.0.4
- found 2.0.4 in filename of file in /nix/store/946hqpkgmb964ilf2sbk9ln4kfy7jnkr-yaws-2.0.4

cc "@goibhniu @the-kenny"