[BUG] 1 untranslated string (donating one sentence and no citation) (de)

[robovoice1]

Describe the bug
A clear and concise description of what the bug is.

If the contributer donates a single sentence (non en) without the citation and submit the sentence, the info "Please fill out this field" pops up (not translated)

To Reproduce
Steps to reproduce the behavior:

1. write a sentence in a non english language
2. Leave the citation field blank
3. Submit the sentence
4. See the not translated info

Expected behavior
A clear and concise description of what you expected to happen.
Translated message

Screenshots
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Mobile (please complete the following information):

• OS: [e.g. iOS] GrapheneOS
• Browser [e.g. chrome, safari] Vanadium
• Version [e.g. 22] 128.0.6613.146