libgringotts: 1.1.2 -> 1.2.1

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

This update was made based on information from https://repology.org/metapackage/libgringotts/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 1.2.1 with grep in /nix/store/9z57bh8m3wr1fjaksavpyjr8y9xanf0l-libgringotts-1.2.1
- directory tree listing: https://gist.github.com/6efcd3f0105df20d27e52a1f3e69b142