backtest as Pipeline's method

[julia-shenshina]

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• Did you read the contribution guide?
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Related Issue

Closing issues

closes #121

[codecov-commenter]

Codecov Report

Merging #161 (ec17383) into master (8d09303) will increase coverage by 0.44%.
The diff coverage is 99.21%.

@@            Coverage Diff             @@
##           master     #161      +/-   ##
==========================================
+ Coverage   87.22%   87.67%   +0.44%     
==========================================
  Files          74       75       +1     
  Lines        3272     3399     +127     
==========================================
+ Hits         2854     2980     +126     
- Misses        418      419       +1     

Impacted Files	Coverage Δ
etna/pipeline/pipeline.py	99.25% <99.13%> (-0.75%)	⬇️
etna/metrics/__init__.py	100.00% <100.00%> (ø)
etna/metrics/utils.py	100.00% <100.00%> (ø)
etna/model_selection/backtest.py	97.60% <100.00%> (+0.03%)	⬆️

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[martins0n]

👍

[iKintosh]

🥇

[iKintosh]

Maybe same format as above?

[julia-shenshina]

what do you mean?

[iKintosh]

:itaksoidet: