xtermcontrol: 3.3 -> 3.4

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

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

These checks were done:

- built on NixOS
- ran ‘/nix/store/2wr7vzki1v1d9za89c4hgsgbbn9j2gzr-xtermcontrol-3.4/bin/xtermcontrol -h’ got 0 exit code
- ran ‘/nix/store/2wr7vzki1v1d9za89c4hgsgbbn9j2gzr-xtermcontrol-3.4/bin/xtermcontrol --help’ got 0 exit code
- found 3.4 with grep in /nix/store/2wr7vzki1v1d9za89c4hgsgbbn9j2gzr-xtermcontrol-3.4
- directory tree listing: https://gist.github.com/d2f87e2d47bdfed0a5727db4c27c83b0