[Bug][Improve][Connector-v2][ElasticsearchSource] Fix behavior when source empty，Support SourceConfig.SOURCE field empty.

[CosmosNi]

[Improve][Connector-v2][ElasticsearchSource] Support SourceConfig.SOURCE field empty.

Purpose of this pull request

Does this PR introduce any user-facing change?

How was this patch tested?

Check list

• If any new Jar binary package adding in your PR, please add License Notice according
  New License Guide
• If necessary, please update the documentation to describe the new feature. https://github.com/apache/seatunnel/tree/dev/docs
• If you are contributing the connector code, please check that the following files are updated:
  1. Update change log that in connector document. For more details you can refer to connector-v2
  2. Update plugin-mapping.properties and add new connector information in it
  3. Update the pom file of seatunnel-dist
• Update the release-note.

[CosmosNi]

@iture123 @TyrantLucifer @Hisoka-X PTAL,thanks.

[Hisoka-X]

I think we should add a e2e test case in

seatunnel/seatunnel-e2e/seatunnel-connector-v2-e2e/connector-elasticsearch-e2e/src/test/java/org/apache/seatunnel/e2e/connector/elasticsearch/ElasticsearchIT.java

Line 68 in 045d3e3

public class ElasticsearchIT extends TestSuiteBase implements TestResource {

[CosmosNi]

@iture123 @TyrantLucifer @Hisoka-X PTAL,thanks.

[Hisoka-X]

Hi @CosmosNi , thanks for add test! Could you retry the test case after merge from dev?

[CosmosNi]

@Hisoka-X I don't understand. Can you show me how to operate it?

[Hisoka-X]

merge code from upstream

[CosmosNi]

@Hisoka-X already merge code from upstream，PTAL,thanks.

[CosmosNi]

@Hisoka-X i add a label (array_column) to handle es array type,PTAL,thanks.

[CosmosNi]

@Hisoka-X @hailin0 @EricJoy2048 PTAL,thanks.

[Hisoka-X]

LGTM

[CosmosNi]

@Hisoka-X sorry，I accidentally removed label.