[l10n] Improve Romanian (ro-RO) and Hungarian (hu-HU) translations

[noraleonte]

• I have followed (at least) the PR section of the contributing guide.

[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
• Clean files with yarn prettier.

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These are the results for the performance tests:

Test case	Unit	Min	Max	Median	Mean	σ
Filter 100k rows	ms	529.2	1,342.8	529.2	873.56	307.498
Sort 100k rows	ms	629.7	984.5	919.8	839.66	144.033
Select 100k rows	ms	215	453.2	299.5	305.96	87.994
Deselect 100k rows	ms	182.9	357.2	258.2	259.18	58.301

Generated by 🚫 dangerJS against 2bea82d