Teach OutliersTransform to ignore holidays

[Polzovat123]

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

1. Add parameters ignore_flag_column: Optional[str] = None -- if set, then it should be column with binary flag of holiday (which might be created from the HolidaysTransform)
2. Update the transform method: now it should ignore the outliers on dates with true values in ignore_flag_column.
3. Update the fit method: now it should check the ignore_flag_column for existence and correctness of the format (binary)

Need to be added:

Need to be fixed:

Closing issues

closes #22
closes #293

[github-actions]

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 90.17%. Comparing base (7dc5665) to head (6c83b12).
Report is 1 commits behind head on master.

❗ Current head 6c83b12 differs from pull request most recent head 95e5129. Consider uploading reports for the commit 95e5129 to get more accurate results

Additional details and impacted files

@@             Coverage Diff             @@
##           master     #291       +/-   ##
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+ Coverage   10.46%   90.17%   +79.70%     
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  Files         203      203               
  Lines       14318    14334       +16     
===========================================
+ Hits         1498    12925    +11427     
+ Misses      12820     1409    -11411     

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