chktex binary doesn't work without its global resource file which
comes in its tlType="run" package. This commit moves chktex into a
separate tlType="bin" package so it is only used along with its
tlType="run" counterpart.

Motivation for this change

Fixes: #10377

Things done

• Tested using sandboxing (nix.useSandbox on NixOS, or option sandbox in nix.conf on non-NixOS linux)
• Built on platform(s)
  • NixOS
  • macOS
  • other Linux distributions
• Tested via one or more NixOS test(s) if existing and applicable for the change (look inside nixos/tests)
• Tested compilation of all pkgs that depend on this change using nix-shell -p nixpkgs-review --run "nixpkgs-review wip"
• Tested execution of all binary files (usually in ./result/bin/)
• Determined the impact on package closure size (by running nix path-info -S before and after)

# nix path-info -Sh `readlink before`
/nix/store/p7ylazwg2zn5g58s5ldp2z8y0kcwjs1h-texlive-combined-small-2019  430.1M
# nix path-info -Sh `readlink after` 
/nix/store/z5vq5mb8zlj05f7nbyqbd1q9irl146mf-texlive-combined-small-2019  430.0M

• Ensured that relevant documentation is up to date
• Fits CONTRIBUTING.md.