Improve Property Mapper Exception message
The current exception message could be improved in order to make bug tracking more simple. The message should read
Exception while property mapping for target type "TYPO3\Media\Domain\Model\Image", at property path "submittedFile": The target type was no string, but of type "NULL"
while it now reads only
Exception while property mapping at property path "submittedFile": The target type was no string, but of type "NULL"
The hint about the target type will make it simpler to know where to search.