Clear or refresh the cache for the sequence generator in Hibernate

Issue

• Support integration of externally supplied ID scenarios with use of Hibernate SequenceGenerator supplied IDs
• Using the default sequence generator to provide identifiers for entities

   @SequenceGenerator(name = "my.entity.seq", sequenceName = "EVENT_SEQ", allocationSize = 10, initialValue = 1)
   @GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "my.entity.seq")

• Inserting data with IDs not supplied by the in-memory generator (i.e. bypassing Hibernate's sequence generator)
• Updating the generator's backing sequence persisted in the database
• Since allocationSize > 0 ¹, need to force a refresh of the generator's cached id