Add inverse transformation into predict method of pipelines

[Mr-Geekman]

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?

Proposed Changes

Look at #1295.

Closing issues

Closes #1295.

[codecov-commenter]

Codecov Report

Merging #1314 (ec536bb) into master (7e54706) will decrease coverage by 82.14%.
The diff coverage is 0.00%.

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@@            Coverage Diff             @@
##           master   #1314       +/-   ##
==========================================
- Coverage   88.83%   6.69%   -82.14%     
==========================================
  Files         192     203       +11     
  Lines       12188   12499      +311     
==========================================
- Hits        10827     837     -9990     
- Misses       1361   11662    +10301     

Impacted Files	Coverage Δ
etna/pipeline/mixins.py	0.00% <0.00%> (-99.16%)	⬇️

... and 196 files with indirect coverage changes

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[github-actions]

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