SpringDataJpaAotDialect must not return null for getSqlAstTranslatorFactory()

[christophstrobl]

Despite the javdoc stating to return null for default StandardSqlAstTranslatorFactory, an error will occur if trace logging is enabled for org.hibernate.orm.

Caused by: java.lang.NullPointerException: 
  Cannot invoke "org.hibernate.sql.ast.SqlAstTranslatorFactory.buildModelMutationTranslator(org.hibernate.sql.model.ast.TableMutation, org.hibernate.engine.spi.SessionFactoryImplementor)" 
  because the return value of "org.hibernate.dialect.Dialect.getSqlAstTranslatorFactory()" is null