ltl2ba: 1.1 -> 1.2b1

Semi-automatic update generated by https://github.com/ryantm/nix-update tools. 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 1.2b1 in filename of file in /nix/store/jx5s7w6bmd6lfqvxl2lly3ggd4k9ncax-ltl2ba-1.2b1