Motivation for this change

This updates ungoogled-chromium. This change was created by manually copying the regular chromium expressions and applying a small diff to support the ungoogled patchset.

Performed a cursory test and everything looks good, except for a slight icon/font rendering issue that also appears in the upstream chromium package.

Includes a possible fix for ungoogled-software/ungoogled-chromium#1050 - renames the nix store path with a suffix of ungoogled-chromium instead of chromium, to hopefully allow the nix-env updater to work properly.

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

cc @danielfullmer