[META] Make it easy to consume next versions of clients

[dblock]

Is your feature request related to a problem?

Trying to test opensearch-project/opensearch-java#177, to consume the next version of opensearch-java I had to make changes to gradle scripts to include shadowJar, build and install the shadowJar. I also had to document how to do it in https://github.com/dblock/opensearch-java-client-demo/tree/opensearch-java-2.1.0. Instead, a snapshot build of opensearch-java-2.1.0 should have been made available automatically.

What solution would you like?

A campaign to figure out ways that anyone can consume the next version of a client.

• [FEATURE] Publish snapshot build opensearch-java#57

Need to figure out what are the other mechanism in every language client and open issues for each that needs work.

What alternatives have you considered?
Instructions on how to build next versions of clients.

Do you have any additional context?
While for Java we need to produce SNAPSHOTS, platforms such as Ruby have a way to reference code with github: 'opensearch-project/opensearch-ruby', so there's nothing to do for the Ruby client.