Warning: This build has drifted.
The coverage report for this pull request build may be inaccurate because its base commit is no longer the HEAD of its target branch.
This means it includes changes from outside the original pull request, including, potentially, unrelated coverage changes.

    • Learn more: For more information on this, see Tracking coverage changes for pull request builds.
    • Fix now: For a quick fix, rebase this PR at GitHub. Your next report should be accurate.
    • Prevent going forward: To avoid this issue with future PRs, see these Recommended CI Configurations.

feat(framework): clean up Volcano PodGroup on TrainJob terminal or suspended state

Add a new optional ComponentDeleterPlugin interface, symmetric to the
existing ComponentBuilderPlugin: a plugin returns objects that should
now be removed for a TrainJob, and the reconciler performs the actual
deletion. It runs on every reconcile regardless of the TrainJob's
status, so a plugin decides for itself whether an object should
currently exist, and must be idempotent.

Volcano implements it to delete its PodGroup once the TrainJob is
Failed, Complete, or suspended, so it stops reserving minResources
capacity in the Volcano queue indefinitely. Volcano.Build() is updated
to skip (re)creating the PodGroup while suspended, so its lifecycle
during suspension is fully owned by Delete() rather than racing with
it.

Adds delete on scheduling.volcano.sh/podgroups to the controller RBAC,
which was missing.

Fixes #4033

Signed-off-by: daehyun-kim-94 <daehyun.kim.0613@gmail.com>