libwacom: 0.28 -> 0.29

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

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

These checks were done:

- built on NixOS
- ran `/nix/store/pdk4f0vsb3ynh1jdvqfinji6grl47m8m-libwacom-0.29/bin/libwacom-list-local-devices -h` got 0 exit code
- ran `/nix/store/pdk4f0vsb3ynh1jdvqfinji6grl47m8m-libwacom-0.29/bin/libwacom-list-local-devices --help` got 0 exit code
- ran `/nix/store/pdk4f0vsb3ynh1jdvqfinji6grl47m8m-libwacom-0.29/bin/libwacom-list-local-devices help` got 0 exit code
- found 0.29 with grep in /nix/store/pdk4f0vsb3ynh1jdvqfinji6grl47m8m-libwacom-0.29
- directory tree listing: https://gist.github.com/cc947710a926712edfc2c49d7f55510b