Spring-ai Add the public access modifier to ElasticsearchVectorStoreAutoConfiguration

Add the public access modifier to ElasticsearchVectorStoreAutoConfiguration class, so that it can be excluded and a custom configuration can be defined.

This makes it consistent with all the other vector store auto configurations classes.

Fixes https://github.com/spring-projects/spring-ai/issues/1462

Comment From: markpollack

thanks, merged in b1377d194dc1ebceb7032431b7ac362358a7e82d