fix(dashboard): use non-deprecated functions + make tests work at night

[susnux]

Summary

1. Use the non deprecated signature of t
2. Added some context for translators as there might be something like "good morning, X" for the night in other languages.
3. Fix tests there is no "Good night" its just "Hello" in English

Checklist

• Code is properly formatted
• Sign-off message is added to all commits
• Tests (unit, integration, api and/or acceptance) are included
• Screenshots before/after for front-end changes
• Documentation (manuals or wiki) has been updated or is not required
• Backports requested where applicable (ex: critical bugfixes)
• Labels added where applicable (ex: bug/enhancement, 3. to review, feature component)
• Milestone added for target branch/version (ex: 32.x for stable32)

AI (if applicable)

• The content of this PR was partly or fully generated using AI

[susnux]

/backport to stable34

[susnux]

/backport to stable33

[backportbot]

The backport to stable33 failed. Please do this backport manually.

# Switch to the target branch and update it
git checkout stable33
git pull origin stable33

# Create the new backport branch
git checkout -b backport/62682/stable33

# Cherry pick the change from the commit sha1 of the change against the default branch
# This might cause conflicts, resolve them
git cherry-pick 3e9ecdd5 c84cdcd7

# Push the cherry pick commit to the remote repository and open a pull request
git push origin backport/62682/stable33

Error: Failed to check for changes with origin/stable33: No changes found in backport branch

---

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

[backportbot]

The backport to stable34 failed. Please do this backport manually.

# Switch to the target branch and update it
git checkout stable34
git pull origin stable34

# Create the new backport branch
git checkout -b backport/62682/stable34

# Cherry pick the change from the commit sha1 of the change against the default branch
# This might cause conflicts, resolve them
git cherry-pick 3e9ecdd5 c84cdcd7

# Push the cherry pick commit to the remote repository and open a pull request
git push origin backport/62682/stable34

Error: Failed to check for changes with origin/stable34: No changes found in backport branch

---

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