[GitHub Request] move opensearch-k8s-operator functional-tests workflow to larger runners

What is the type of request?

No response

Details of the request

The functional-tests GitHub Actions job consistently fails because the default GitHub-hosted default runners cannot host an entire OpenSearch cluster plus the upgrade scenarios we run in CI. During provisioning/upgrade the job runs out of disk and is terminated. We need to move this workflow onto larger infrastructure so tests are reliable.

i.e. stand up self-hosted runners for the heavy job

• Provision a VM (or small pool) with spec bigger than standard Github runner size and register it as a runner with labels like self-hosted, linux, large.
• Limit the runner scope to this repo and dedicate it to functional tests only.
• Keep all other jobs (lint, unit tests, docs) on GitHub-hosted runners so we don’t waste dedicated resources on lightweight tasks.

Additional information to support your request

This is a blocker for merging open PRs in https://github.com/opensearch-project/opensearch-k8s-operator. CI job for operator functional tests always fails because of disk lack.

When does this request need to be completed?

No specific timeline, but the sooner the better.

Notes

Track the progress of your request here: https://github.com/orgs/opensearch-project/projects/208/views/33.
Member of @opensearch-project/admin will take a look at the request soon.
Thanks!

Start by inspecting the opensearch-k8s-operator functional-tests GitHub Actions workflow and its current runner configuration. Check how self-hosted runners are provisioned and scoped, then verify that only the heavy functional-tests job uses larger infrastructure while lint, unit tests, and docs remain on GitHub-hosted runners. Done means the functional tests complete without disk exhaustion.