firefoxPackages.tor-browser*, tor-browser-bundle: remove

These are all based on firefox versions with known vulnerabilities
exploited in the wild.

We seriously shouldn't ship this in nixpkgs, especially not for
sensitive applications as the Tor Browser.

`tor-browser-bundle` is just a wrapper around
`firefoxPackages.tor-browser`, so let's remove it too.

`tor-browser-bundle-bin` is the much safer bet, which is individually
downloaded from `dist.torproject.org` and just `patchelf`-ed locally to
work on NixOS.

Co-Authored-By: Alyssa Ross <hi@alyssa.is>
Co-Authored-By: Andreas Rammhold <andreas@rammhold.de>
Co-Authored-By: Graham Christensen <graham@grahamc.com>