babl: 0.1.46 -> 0.1.48

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

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

These checks were done:

- built on NixOS

- 0 of 0 passed binary check by having a zero exit code.
- 0 of 0 passed binary check by having the new version present in output.
- found 0.1.48 with grep in /nix/store/1pffxdly3bs42aqxf9zzmh3kcn304r8i-babl-0.1.48
- directory tree listing: https://gist.github.com/42f46e6f60e3db18a7a54f4ec1c31b80
- du listing: https://gist.github.com/3382dcb9c594fd5e06a9432be1c8d80b