Update black rev in order to include fix for https://github.com/psf/black/issues/1629

[tafaRU]

I ran into this error related to psf/black#1629.
In order to fix it, black needs to be updated at least to https://pypi.org/project/black/21.4b0.

[simahawk]

this is the repo's config. I guess you want to change this instead https://github.com/OCA/oca-addons-repo-template/blob/master/src/.pre-commit-config.yaml.jinja#L4 ?

[tafaRU]

Ok, thanks for the advice @simahawk!

[joao-p-marques]

This can be a dangerous change in branches bellow v15, as it can introduce some code formatting changes. We did hold back on bumping the version before for this reason, so maybe @sbidoul and @yajo should comment on this and say if they are OK with it.

[sbidoul]

The problem with changing black on active branches is that it creates some churn with PRs becoming red due to minor reformating. That said, black is getting more and more stable over time.

Alternatives:

• using the # fmt: on/off/skip black directive to work around local issues
• making the black version a copier question (with same defaults as today), so we can let PSCs manage their black version autonomously across branches

[tafaRU]

Ok, thanks for the explanation.
In the meantime I found the lines could make black fail and I fix them. So I can proceed without this.

Personally I'd prefer the following:

making the black version a copier question (with same defaults as today), so we can let PSCs manage their black version autonomously across branches