[nova] 'pre-commit' integration

This is a heads up that I've proposed a patch to integrate [1] to add support for the 'pre-commit' tool [2] in nova. As noted in that change, this provides a faster, most automated alternative to the 'fast8' tox target we currently use for validating recently changed code. While this is opt-in, I'm also proposing deprecating the 'fast8' behavior since I don't think it's necessary with pre-commit support. As a result, it would be good if anyone that has an opinion on the matter took a look at the change.

Have a good weekend, Stephen

[1] https://review.opendev.org/665518 [2] https://pre-commit.com/