Pruning the email log can fail due to too many placeholders

[dtdesign]

https://github.com/WoltLab/WCF/blob/dd0d4ddd18178cc7366bbb20e5377d230a2034b4/wcfsetup/install/files/lib/data/email/log/entry/EmailLogEntryAction.class.php#L29-L41

This query has no limit on the number of placeholders, potentially yielding more IDs than the permitted number of placeholders.