[hooks] don't insert an owned_by relation for deleted entities
If, in the same transaction, a composed entity is created and deleted,
we'll have scheduled a SyncOwnersOp which would end up creating an
owned_by relation for the deleted entity. Closes #4846883
addressbook
basket
blog
book
calendar
comment
company
email
file
folder
i18ncontent
keyword
link
mailinglist
person
tag
timeseries
vcsfile