fix bug: IndexQuery's id get ignored in bulkIndexOperation

[scoobyzhang]

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Closes #2405

[sothawo]

Thank you for finding and fixing this.

Can you please add tests to the org.springframework.data.elasticsearch.core.ElasticsearchIntegrationTests class that verify the fixed behaviour (and prove the wrong behaviour before the change)?

[scoobyzhang]

@sothawo Thanks for your reply. I've pushed another commit with the test, please check it.