Room results are incorrect case of using foreach instead of Room relationships

[axrkozlov]

In Room there are approaches that could be used to define the relations between the entities:

1. @Embedded (nested objects)
2. @foreignkey
3. @relation
   In test should have been using relationship instead of two sequential request and foreach to bind a library to a book. My simple read results with foreach are about 400ms comparing to using @Embedded relationship they are 30ms.