(7.0.z) Some tests fail because oracle doesn't support single column identity table

This issue is similar to JBEAP-3455.

org.hibernate.test.converter.map.MapKeyAttributeConverterTest (classMethod) fails with oracle11g
org.hibernate.id.FlushIdGenTest (testPersistBeforeTransaction) fails with oracle12c
org.hibernate.test.annotations.xml.hbm.HbmWithIdentityTest (testManyToOneAndInterface) fails with oracle12c