New base class for transforms

[alex-hse-repository]

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 #797.

Closing issues

Closes #797

[github-actions[bot]]

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[codecov-commenter]

Codecov Report

:exclamation: No coverage uploaded for pull request base (tsdataset_2@dc8d48a). Click here to learn what that means. The diff coverage is n/a.

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