[l10n] Improve Japanese (ja-JP) locale

[makoto14]

This PR adds the missing translation for the Japanese (ja-JP) locale - #3211.

[mui-bot]

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These are the results for the performance tests:

Test case	Unit	Min	Max	Median	Mean	σ
Filter 100k rows	ms	-197.7	14.4	-42.5	-81.86	94.499
Sort 100k rows	ms	631.9	1,414.9	1,293.2	1,137.64	273.705
Select 100k rows	ms	670.1	709.2	697	691.12	14.819
Deselect 100k rows	ms	96.7	191.8	185.4	166.18	35.323

Generated by 🚫 dangerJS against 659c6d9

[oliviertassinari]

@makoto14 Thanks