feat(translations): add german language

[Hypnotist1148]

Link to Jira Ticket

https://formio.atlassian.net/browse/FIO-10611

Description

What changed?

This PR adds translations for the german language.

Why have you chosen this solution?

Because it matches the english translations.

Breaking Changes / Backwards Compatibility

This PR should not include breaking changes or impact backwards compatibility.

Dependencies

No dependencies were added.

How has this PR been tested?

I have not added any automated changes as this is only a translation.

Checklist:

• I have completed the above PR template
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation (if applicable)
• My changes generate no new warnings
• My changes include tests that prove my fix is effective (or that my feature works as intended)
• New and existing unit/integration tests pass locally with my changes
• Any dependent changes have corresponding PRs that are listed above

[Hypnotist1148]

We (ÖAMTC) talked with some of your colleagues about implementing german translations in Form.io, thus this PR was created.