Use eslint

[dominik-zeglen]

I want to merge this change because tslint is deprecated and this fixes memory leaks and speeds up linting a little bit.

Pull Request Checklist

1. All visible strings are translated with proper context.
2. All data-formatting is locale-aware (dates, numbers, and so on).
3. Translated strings are extracted to .pot file.
4. Number of API calls is optimized.
5. The changes are tested.
6. Type definitions are up to date.
7. Changes are mentioned in the changelog.

[codecov]

Codecov Report

Merging #285 into master will decrease coverage by 0.04%.
The diff coverage is 36.84%.

@@            Coverage Diff             @@
##           master     #285      +/-   ##
==========================================
- Coverage   73.97%   73.93%   -0.05%     
==========================================
  Files         606      606              
  Lines        6521     6525       +4     
  Branches     1072     1072              
==========================================
  Hits         4824     4824              
- Misses       1510     1514       +4     
  Partials      187      187

Impacted Files	Coverage Δ
.../storybook/stories/components/MultiSelectField.tsx	100% <ø> (ø)	⬆️
...pleteSelectField/SingleAutocompleteSelectField.tsx	82.14% <ø> (ø)	⬆️
...components/VoucherCreatePage/VoucherCreatePage.tsx	87.5% <ø> (ø)	⬆️
...nslationsEntitiesList/TranslationsEntitiesList.tsx	73.33% <ø> (ø)	⬆️
src/components/RichTextEditor/RichTextEditor.tsx	66.66% <ø> (ø)	⬆️
src/fixtures.ts	36.58% <ø> (ø)	⬆️
src/customers/fixtures.ts	100% <ø> (ø)	⬆️
src/components/MenuToggle.tsx	75% <ø> (ø)	⬆️
...storybook/stories/components/SingleSelectField.tsx	100% <ø> (ø)	⬆️
...s/components/ProductVariantCreateDialog/reducer.ts	85.93% <ø> (ø)	⬆️
... and 15 more

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