Add getDataSource method to DefaultBatchConfigurer

[acktsap]

When customizing createJobRepository using DefaultBatchConfiguer (according to official docs), it force us to use DataSource bean explicitly.

@Bean
public BatchConfigurer batchConfigurer(DataSource dataSource) {
	return new DefaultBatchConfigurer() {
		@Override
		protected JobRepository createJobRepository() throws Exception {
			JobRepositoryFactoryBean factory = new JobRepositoryFactoryBean();
			factory.setDataSource(dataSource);
			factory.setTransactionManager(getTransactionManager());
			factory.setTablePrefix("SYSTEM.TEST_");
			factory.afterPropertiesSet();
			return factory.getObject();
		}
	};
}

Using getDataSource() method, we can use like this.

@Bean
public BatchConfigurer batchConfigurer() {
	return new DefaultBatchConfigurer() {
		@Override
		protected JobRepository createJobRepository() throws Exception {
			JobRepositoryFactoryBean factory = new JobRepositoryFactoryBean();
			factory.setDataSource(getDataSource());
			factory.setTransactionManager(getTransactionManager());
			factory.setTablePrefix("SYSTEM.TEST_");
			factory.afterPropertiesSet();
			return factory.getObject();
		}
	};
}

[fmbenhassine]

Rebased and merged as 26fc468. Thank you for your contribution.