fix: log ignored workspace propfind exceptions at debug

[joshtrichards]

📝 Summary

In case needed to troubleshoot situations involving permissions, locking, etc. Addresses post-merger review comments:

#5948 (comment)

#6155 (comment)

🖼️ Screenshots

🏚️ Before	🏡 After
B	A

🚧 TODO

• ...

🏁 Checklist

• Code is properly formatted (npm run lint / npm run stylelint / composer run cs:check)
• Sign-off message is added to all commits
• Tests (unit, integration and/or end-to-end) passing and the changes are covered with tests
• Documentation (README or documentation) has been updated or is not required

[joshtrichards]

/backport to stable30

[joshtrichards]

/backport to stable29

[backportbot]

The backport to stable29 failed. Please do this backport manually.

# Switch to the target branch and update it
git checkout stable29
git pull origin stable29

# Create the new backport branch
git checkout -b backport/6675/stable29

# Cherry pick the change from the commit sha1 of the change against the default branch
# This might cause conflicts, resolve them
git cherry-pick 9df5c08a

# Push the cherry pick commit to the remote repository and open a pull request
git push origin backport/6675/stable29

Error: No changes found in backport branch

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