Content importer does not deal correctly with unresolvable references and omits further (necessary processing steps)

[zopyx]

We have content-types that contains a RelationChoice field with a value like

related_url': '/community/meinung/onlineangebote-lehramtsstudium'

The referenced object has not been imported yet. So this reference is not resolvable. For this reason, the deserializer throws an error

> /Users/ajung/src/plone6.buildout/src/collective.exportimport/src/collective/exportimport/import_content.py(366)import_new_content()
-> new = deserializer(validate_all=False, data=item)
(Pdb) 
zExceptions.BadRequest: [{'message': 'Could not resolve object for path=/community/meinung/onlineangebote-lehramtsstudium', 'field': 'related_url', 'error': 'ValidationError'}]

and stops with the further processing on the object. E.g. the review state of this object is then not correctly set (and remains in private rather than published state).

[zopyx]

Removing continue in https://github.com/collective/collective.exportimport/blob/main/src/collective/exportimport/import_content.py#L368 resolves the problem for us...perhaps it is the solution since the import of relations is usually done at the end of a migration import.

[zopyx]

Alternatively, the deserializer check could be made optional (through a parameter or environment variable).