[l10n] Improve Chinese (zh-CN) and Chinese(traditional) (zh-TW) locales

[MyNameIsTakenOMG]

This PR adds the missing translation for the zhCN and zhTW locales requested in #3211

[mui-bot]

Localization writing tips ✍️

Seems you are updating localization 🌍 files.

Thank you for contributing to the localization! 🎉 To make your PR perfect, here is a list of elements to check: ✔️

• Verify if the PR title respects the release format. Here are two examples (depending if you update or add a locale file)

  [l10n] Improve Swedish (sv-SE) locale
  [l10n] Add Danish (da-DK) locale

• Update the documentation of supported locales by running yarn l10n
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These are the results for the performance tests:

Test case	Unit	Min	Max	Median	Mean	σ
Filter 100k rows	ms	319.1	511.6	414.5	406.94	77.371
Sort 100k rows	ms	762.4	1,456.8	1,441	1,252.2	254.802
Select 100k rows	ms	636.6	827	719.6	734.56	72.543
Deselect 100k rows	ms	95.8	277.4	226.3	195.16	62.184

Generated by 🚫 dangerJS against 3e6b31c

[oliviertassinari]

@MyNameIsTakenOMG Thanks!

[MyNameIsTakenOMG]

@MyNameIsTakenOMG Thanks!

My pleasure to make a contribution to the community☺👍

[oliviertassinari]

@DanailH This makes me think of an automation opportunity, we could automatically apply GitHub labels based on which file are changed in Core, X. https://www.notion.so/mui-org/GitHub-community-issues-PRs-Tier-1-12a84fdf50e44595afc55343dac00fca?pvs=4#7aff02318a2d47e8b180f14c6cfc55b8, an idea for Michel.