Add `blacken-docs` and `pyupgrade` to pre-commit configuration

[Takishima]

NB: need to wait for #440 to be merged to address the CI failures.

[coveralls]

Pull Request Test Coverage Report for Build 2650076144

• 125 of 125 (100.0%) changed or added relevant lines in 38 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.01%) to 100.0%

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Totals
Change from base Build 2645920709:	0.01%
Covered Lines:	6997
Relevant Lines:	6997

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💛 - Coveralls