liquibase: 3.5.5 -> 3.6.0

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

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

These checks were done:

- built on NixOS
- Warning: no binary found that responded to help or version flags. (This warning appears even if the package isn't expected to have binaries.)
- found 3.6.0 with grep in /nix/store/q0h0dm35qda3vls6axin875ky93n0idg-liquibase-3.6.0
- directory tree listing: https://gist.github.com/d7568f9f2cd317086e4b519f4749b8d8