minor #35850 [Validator] Add missing translations (fabpot)

This PR was merged into the 5.1-dev branch.

Discussion
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[Validator] Add missing translations

| Q             | A
| ------------- | ---
| Branch?       | 3.4
| Bug fix?      | yes
| New feature?  | no <!-- please update src/**/CHANGELOG.md files -->
| Deprecations? | no <!-- please update UPGRADE-*.md and src/**/CHANGELOG.md files -->
| Tickets       | n/a <!-- prefix each issue number with "Fix #", if any -->
| License       | MIT
| Doc PR        | n/a

Backport translations for 5.1.

Commits
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a902186 [Validator] Add missing translations