Within a delete resolvers, deleting > 1 item fails in the eventhook

[rizzza]

Describe the bug
Say for example, we are deleting an annotationNamespace and all of it's associated annotations within one call to the ent client.

r.client.Annotation.Delete().Where(annotation.AnnotationNamespaceID(id)).Exec(ctx)

The eventhook for the annotation delete will fail because it is expecting only a singular deletion.

We receive the following error

"object doesn't have an id "

To Reproduce
Code up a delete resolver to delete all based on some predicate

Expected behavior
For the delete eventhook to be able to handle > 1 deletions of an thing at a time, rather than having to iterate and DeleteOne(id) at a time within the resolver.

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Additional context
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