Translations: Update Polish

[janisz]

I found translations that look weird for native speaker

• credentials could be translated as poświadczenie but it's quite official term and mean something like a certificate not login data (dane logowania).
• To save somebody means to rescue so Person saved translated to Osoba uratowana means Person rescued. We should have Osoba zapisana like with other <Object> saved items.

[CLAassistant]

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[janisz]

@wikiyu @graciousgrey Can you take a look?

[wikiyu]

@janisz looks great, mechanical translations have been fixed.

[lastzero]

Thanks! ⭐