Add black, isort and pre-commit

[pilot7747]

Improve development experience with pre-commit, black formatter, and isort.

Checklist

• [x] I have read the CONTRIBUTING document
• [x] I hereby agree to the terms of the CLA available at: https://yandex.ru/legal/cla/?lang=en
• [ ] My change requires a change to the documentation
• [ ] I have updated the documentation accordingly
• [ ] I have added tests to cover my changes
• [x] All new and existing tests passed

[codecov-commenter]

Codecov Report

Attention: 46 lines in your changes are missing coverage. Please review.

Comparison is base (e9b83b5) 93.01% compared to head (2e36dae) 93.01%.

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Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #85 +/- ## ======================================= Coverage 93.01% 93.01% ======================================= Files 47 47 Lines 2019 2019 ======================================= Hits 1878 1878 Misses 141 141 ``` | [Files](https://app.codecov.io/gh/Toloka/crowd-kit/pull/85?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=Toloka) | Coverage Δ | | |---|---|---| | [crowdkit/\_\_init\_\_.py](https://app.codecov.io/gh/Toloka/crowd-kit/pull/85?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=Toloka#diff-Y3Jvd2RraXQvX19pbml0X18ucHk=) | `100.00% <100.00%> (ø)` | | | [crowdkit/aggregation/\_\_init\_\_.py](https://app.codecov.io/gh/Toloka/crowd-kit/pull/85?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=Toloka#diff-Y3Jvd2RraXQvYWdncmVnYXRpb24vX19pbml0X18ucHk=) | `66.66% <100.00%> (ø)` | | | [crowdkit/aggregation/base/\_\_init\_\_.py](https://app.codecov.io/gh/Toloka/crowd-kit/pull/85?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=Toloka#diff-Y3Jvd2RraXQvYWdncmVnYXRpb24vYmFzZS9fX2luaXRfXy5weQ==) | `75.00% <100.00%> (ø)` | | | [crowdkit/aggregation/classification/\_\_init\_\_.py](https://app.codecov.io/gh/Toloka/crowd-kit/pull/85?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=Toloka#diff-Y3Jvd2RraXQvYWdncmVnYXRpb24vY2xhc3NpZmljYXRpb24vX19pbml0X18ucHk=) | `100.00% <100.00%> (ø)` | | | [crowdkit/aggregation/classification/dawid\_skene.py](https://app.codecov.io/gh/Toloka/crowd-kit/pull/85?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=Toloka#diff-Y3Jvd2RraXQvYWdncmVnYXRpb24vY2xhc3NpZmljYXRpb24vZGF3aWRfc2tlbmUucHk=) | `95.62% <100.00%> (ø)` | | | [...t/aggregation/classification/gold\_majority\_vote.py](https://app.codecov.io/gh/Toloka/crowd-kit/pull/85?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=Toloka#diff-Y3Jvd2RraXQvYWdncmVnYXRpb24vY2xhc3NpZmljYXRpb24vZ29sZF9tYWpvcml0eV92b3RlLnB5) | `100.00% <100.00%> (ø)` | | | [crowdkit/aggregation/classification/kos.py](https://app.codecov.io/gh/Toloka/crowd-kit/pull/85?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=Toloka#diff-Y3Jvd2RraXQvYWdncmVnYXRpb24vY2xhc3NpZmljYXRpb24va29zLnB5) | `92.50% <100.00%> (ø)` | | | [crowdkit/aggregation/classification/m\_msr.py](https://app.codecov.io/gh/Toloka/crowd-kit/pull/85?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=Toloka#diff-Y3Jvd2RraXQvYWdncmVnYXRpb24vY2xhc3NpZmljYXRpb24vbV9tc3IucHk=) | `97.97% <100.00%> (ø)` | | | [...owdkit/aggregation/classification/majority\_vote.py](https://app.codecov.io/gh/Toloka/crowd-kit/pull/85?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=Toloka#diff-Y3Jvd2RraXQvYWdncmVnYXRpb24vY2xhc3NpZmljYXRpb24vbWFqb3JpdHlfdm90ZS5weQ==) | `100.00% <100.00%> (ø)` | | | [crowdkit/aggregation/classification/wawa.py](https://app.codecov.io/gh/Toloka/crowd-kit/pull/85?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=Toloka#diff-Y3Jvd2RraXQvYWdncmVnYXRpb24vY2xhc3NpZmljYXRpb24vd2F3YS5weQ==) | `100.00% <100.00%> (ø)` | | | ... and [36 more](https://app.codecov.io/gh/Toloka/crowd-kit/pull/85?src=pr&el=tree-more&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=Toloka) | |

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