Stickler-ci

[fmaussion]

The last time stickler had a look at our PRs is 8 days ago (#2415) : https://stickler-ci.com/repositories/26661-pydata-xarray

It looks like their bot is broken: https://github.com/stickler-ci

This is not very trustworthy - we could consider switching to https://pep8speaks.com/ maybe

[fujiisoup]

I set up pep8speaks.
It is now working for every new PR, without merging #2462.

See settings > Integrations and Services
https://github.com/pydata/xarray/settings/installations

I am not yet sure whether it matches to our requirement. Let's see how well it works for a few weeks :)

[max-sixty]

Weirdly, it's still working on pandas-gbq fine: googleapis/python-bigquery-pandas#225