feat(pure-cell): replace flex gap to margins for correct work on ios13

[Romkaf]

Опишите проблему

Не применяются отступы(gap) для чалдов flex контейнера компонента PureCell на ios13 и ниже.
https://caniuse.com/?search=flex-gap

Шаги для воспроизведения

1. Открыть https://core-ds.github.io/core-components/master/?path=/docs/components-cells-purecell--pure-cell
   на ios13

Ожидаемое поведение

Отступы остаются на ios13 и ниже.

[changeset-bot]

⚠️ No Changeset found

Latest commit: 02339b7

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[coveralls]

Pull Request Test Coverage Report for Build 3901707307

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 80.686%

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Totals
Change from base Build 3880599043:	0.0%
Covered Lines:	7309
Relevant Lines:	8259

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💛 - Coveralls

[core-ds-bot]

Собрана новая демка.

[v-gevak]

А точно ли оно нужно @SiebenSieben? Около 1% сидят на 13 iOS

[Romkaf]

По официальной статистики пользаков АО 12 - 22.4K, 13 - 13.8K
даже если это 1%, нужно сделать по уму

[Romkaf]

3,38% по последней инфо)

[v-gevak]

По официальной статистики пользаков АО 12 - 22.4K, 13 - 13.8K даже если это 1%, нужно сделать по уму

Жеска