Docs: Document updates will add duplicate indexes

[realLiangshiwei]

abp/modules/docs/src/Volo.Docs.Domain/Volo/Docs/Documents/FullSearch/Elastic/ElasticDocumentFullSearch.cs

Line 63 in 3842c05

var existsResponse = await client.DocumentExistsAsync(DocumentPath<EsDocument>.Id(document.Id),

abp/modules/docs/src/Volo.Docs.Domain/Volo/Docs/Documents/FullSearch/Elastic/ElasticDocumentFullSearch.cs

Line 70 in 3842c05

Id = NormalizeField(document.Id),

https://www.elastic.co/guide/en/elasticsearch/reference/current/docs-index_.html

Adds a JSON document to the specified data stream or index and makes it searchable. If the target is an index and the document already exists, the request updates the document and increments its version.

We just need to use index API, if the document already exists, it will update the document.