doc fix

[yuhuizhaocom]

use upsert in

    <dependency>
        <groupId>co.elastic.clients</groupId>
        <artifactId>elasticsearch-java</artifactId>
        <version>9.0.0</version>
    </dependency>

will get
Exception in thread "main" co.elastic.clients.elasticsearch._types.ElasticsearchException: [es/update] failed: [action_request_validation_exception] Validation Failed: 1: script or doc is missing;
may replace with doc .

[cla-checker-service]

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154fc9d

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[l-trotta]

Hey @yuhuizhaocom thanks for the fix! If you sign the CLA we can merge this.