tbb: 2018_U3 -> 2018_U4

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

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

These checks were done:

- built on NixOS

- 0 of 0 passed binary check by having a zero exit code.
- 0 of 0 passed binary check by having the new version present in output.
- found 2018_U4 with grep in /nix/store/bi7ml1lf51x1pvf8c9q9sg1vgyr93i10-tbb-2018_U4
- directory tree listing: https://gist.github.com/0b2f954042266f19cb4e819607e57c03
- du listing: https://gist.github.com/f115812285d438e3dc88112762777976