Incorporates the proposed solution in mongodb/laravel-mongodb#2783 to not default $ownerKey to the current model's key name when constructing a MorphTo in HybridRelations::morphTo().
That change alone caused RelationsTest::testMorph() to fail, since MorphTo::addConstraints() would attempt to use a null ownerKey value. This required an additional change to fall back to the foreign key name when building the constraint.
https://jira.mongodb.org/browse/PHPORM-175
Incorporates the proposed solution in mongodb/laravel-mongodb#2783 to not default $ownerKey to the current model's key name when constructing a MorphTo in HybridRelations::morphTo().
That change alone caused RelationsTest::testMorph() to fail, since MorphTo::addConstraints() would attempt to use a null ownerKey value. This required an additional change to fall back to the foreign key name when building the constraint.
Checklist