CI: cleanup style check

[madsbk]

This PR clean up the style check output by capturing both stdout and stderr.
Also isort line-length is now 88, which is what black and flake8 use.

[codecov-io]

Codecov Report

Merging #477 (02c5f49) into branch-0.18 (6e6d868) will increase coverage by 0.17%.
The diff coverage is 100.00%.

@@               Coverage Diff               @@
##           branch-0.18     #477      +/-   ##
===============================================
+ Coverage        90.23%   90.40%   +0.17%     
===============================================
  Files               15       15              
  Lines             1126     1126              
===============================================
+ Hits              1016     1018       +2     
+ Misses             110      108       -2     

Impacted Files	Coverage Δ
dask_cuda/__init__.py	100.00% <100.00%> (ø)
dask_cuda/cuda_worker.py	77.01% <100.00%> (ø)
dask_cuda/explicit_comms/comms.py	99.00% <100.00%> (ø)
dask_cuda/proxy_object.py	87.79% <100.00%> (+0.67%)	⬆️

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[quasiben]

Thanks @madsbk

[jakirkham]

Thanks Mads! 😄

Tried to fix this a while back ( #350 ), but ran into issues 😅 Guess the linter tools were too old

[pentschev]

Sorry for the late review here, but why did we pin those versions specifically instead of those from the integration repo (see https://github.com/rapidsai/integration/blob/branch-0.18/conda/recipes/versions.yaml) ?

[jakirkham]

I think some of these tools weren't respecting line length configuration values in some cases. Ran into similar issues as well. Though this does a raise a good point, would be good to propagate these version bumps into the integration repo.

[pentschev]

Ideas on what's the right approach? Pinning those exact versions in integration will probably lead all other RAPIDS repos to require some reformatting.