[RELEASE] Alignment with OpenSearch 3.0.0 GA

[Xtansia]

Context

The OpenSearch 3.0.0 GA release is currently scheduled for 2025/05/06: opensearch-project/opensearch-build#3747
As such there will be desire for the clients which are generated from this specification to be aligned with this major release. Thus is it is important to ensure the specification itself is largely aligned with 3.0.0.

Tasks

Before 3.0.0 GA

• Update the integration test matrix to use 3.0.0-beta1 instead of 3.0.0-alpha1 (There's a currently open PR beginning to address this). Additionally implement any fixes related to testing against 3.0.0-beta1.
• Run through 3.0.0-beta1 release notes to check listed breaking changed for any that might have been missed in the specification.

After 3.0.0 GA

• Update the integration test matrix to use 3.0.0 instead of 3.0.0-beta1/3.0.0-alpha1. Additionally implement any fixes related to testing against 3.0.0.
• Re-check 3.0.0 release notes for any new changes since beta1.
• Cut a tagged release of the specification

[Xtansia]

@dblock @nhtruong What are your thoughts on if we tag another release of the spec? Do you think next should be another v0.x or should we start a v1.x line?

[nhtruong]

What purpose do the tagged releases for the specs serve right now?

I know that in the future, once all APIs have been backfilled, we can start tagging this repo by major releases of OS so that we can generate clients for specific major versions (to avoid conflicts between major versions).

I think we should keep the 0.x tagging for now. 1.x, 2.x, and so on, should be reserved for when we can match the OS version once the specs are completely filled.

[dblock]

I think we should tag a 0.x and make a release to have a checkpoint.