fix(i18n): Fixed grammar

[rakekniven]

Reported at Transifex.

[github-actions]

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[blizzz]

/backport to stable0.7

[backportbot]

The backport to stable0.7 failed. Please do this backport manually.

# Switch to the target branch and update it
git checkout stable0.7
git pull origin stable0.7

# Create the new backport branch
git checkout -b backport/990/stable0.7

# Cherry pick the change from the commit sha1 of the change against the default branch
# This might cause conflicts, resolve them
git cherry-pick 77f85ea6 3b95e00d

# Push the cherry pick commit to the remote repository and open a pull request
git push origin backport/990/stable0.7

Error: No changes found in backport branch

---

Learn more about backports at https://docs.nextcloud.com/server/stable/go.php?to=developer-backports.

[blizzz]

Ah, already there 👍