Bump black from 21.5b0 to 21.5b1 in /requirements (#17120)
Bump black from 21.5b0 to 21.5b1 in /requirements (#17120)

Bumps [black](https://github.com/psf/black) from 21.5b0 to 21.5b1.
- [Release notes](https://github.com/psf/black/releases)
- [Changelog](https://github.com/psf/black/blob/main/CHANGES.md)
- [Commits](https://github.com/psf/black/commits)

Signed-off-by: dependabot[bot] <5bdcd3c0d4d24ae3e71b3b452a024c6324c7e4bb@github.com>

Co-authored-by: dependabot[bot] <1c358da00a777d4e9898c1280ab801e2df165188@users.noreply.github.com>
bqbn/addons-server,wagnerand/addons-server,mozilla/olympia,wagnerand/addons-server,mozilla/addons-server,wagnerand/addons-server,diox/olympia,mozilla/olympia,bqbn/addons-server,diox/olympia,bqbn/addons-server,mozilla/addons-server,mozilla/addons-server,mozilla/addons-server,diox/olympia,bqbn/addons-server,diox/olympia,mozilla/olympia,wagnerand/addons-server,mozilla/olympia