add flake8-comprehentions

[iKintosh]

IMPORTANT: Please do not create a Pull Request without creating an issue first.

Before submitting (must do checklist)

• Did you read the contribution guide?
• Did you update the docs? We use Numpy format for all the methods and classes.
• Did you write any new necessary tests?
• Did you update the CHANGELOG?

Type of Change

• Examples / docs / tutorials / contributors update
• Bug fix (non-breaking change which fixes an issue)
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[github-actions]

🚀 Deployed on https://deploy-preview-689--etna-docs.netlify.app

[codecov-commenter]

Codecov Report

Merging #689 (eb46e31) into master (be1b719) will decrease coverage by 0.24%.
The diff coverage is 60.00%.

@@            Coverage Diff             @@
##           master     #689      +/-   ##
==========================================
- Coverage   83.79%   83.54%   -0.25%     
==========================================
  Files         119      119              
  Lines        6479     6479              
==========================================
- Hits         5429     5413      -16     
- Misses       1050     1066      +16     

Impacted Files	Coverage Δ
etna/analysis/plotters.py	21.27% <0.00%> (ø)
etna/transforms/timestamp/special_days.py	97.59% <0.00%> (ø)
etna/datasets/tsdataset.py	90.08% <100.00%> (ø)
etna/ensembles/base.py	100.00% <100.00%> (ø)
etna/transforms/feature_selection/base.py	100.00% <100.00%> (ø)
etna/transforms/missing_values/resample.py	96.42% <100.00%> (ø)
etna/transforms/utils.py	100.00% <100.00%> (ø)
etna/libs/tsfresh/distribution.py	33.33% <0.00%> (-50.01%)	⬇️
etna/libs/tsfresh/significance_tests.py	18.84% <0.00%> (-13.05%)	⬇️
etna/libs/tsfresh/relevance.py	72.38% <0.00%> (-3.81%)	⬇️

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[alex-hse-repository]

Why do you decide to ignore C408?

[iKintosh]

Because in cases like this

etna/etna/models/nn/deepar.py

Lines 133 to 139 in be1b719

	trainer_kwargs = dict(
	logger=tslogger.pl_loggers,
	max_epochs=self.max_epochs,
	gpus=self.gpus,
	checkpoint_callback=False,
	gradient_clip_val=self.gradient_clip_val,
	)

It would be easier to read dict(key=value) approach, than {"key": value} in my opinion

[iKintosh]

What do you think?

[alex-hse-repository]

👍