mate.mate-notification-daemon: 1.20.0 -> 1.20.1

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

This update was made based on information from https://repology.org/metapackage/mate-notification-daemon/versions.

These checks were done:

- built on NixOS
- Warning: no invocation of /nix/store/fgg4hxmh9x48wbxh0y07593193427q3n-mate-notification-daemon-1.20.1/bin/mate-notification-properties had a zero exit code or showed the expected version
- Warning: no invocation of /nix/store/fgg4hxmh9x48wbxh0y07593193427q3n-mate-notification-daemon-1.20.1/bin/.mate-notification-properties-wrapped had a zero exit code or showed the expected version
- 0 of 2 passed binary check by having a zero exit code.
- 0 of 2 passed binary check by having the new version present in output.
- found 1.20.1 with grep in /nix/store/fgg4hxmh9x48wbxh0y07593193427q3n-mate-notification-daemon-1.20.1
- directory tree listing: https://gist.github.com/7f852125c1c6ce059b96b1278be2dc41
- du listing: https://gist.github.com/2fda2f0e9255e9383b2611f3eb16f78c