Improve handling of type conversion for data matching #55
Description
Related to #27 - doctrine/orm does a pretty job type-juggling when it's safe to do so. Notably, if you have an Id property defined as an int and the $em->find(Model::class, "123"), it's able to generally figure this out. Mocktrine is a fair bit stricter in the matching, so code that works at runtime may fail in tests.