fix a race in the test 'a Realm can be reset twice' (#5820)
fix a race in the test 'a Realm can be reset twice' (#5820)

The client reset test harness expects an object to be added
and this object is already there from the first reset, so
we also need to wait for a value field to persist before
continuing.
realm/realm-core,realm/realm-core,realm/realm-core,realm/realm-core,realm/realm-core,realm/realm-core,realm/realm-core