Overview
When using the BulkImport module with the combination of PHP 8.1.29 and Omeka S version 4.0.4, the following error occurred.
I have not been able to identify the root cause at this point, but I will describe the workaround.
Workaround
By using BulkImport v3.4.51 below, the above error no longer occurred.
https://github.com/Daniel-KM/Omeka-S-module-BulkImport/releases/tag/3.4.51
Summary
I hope this is helpful.