Function handle_despawn_worker_within 

pub(crate) fn handle_despawn_worker_within(
    workspace: &Arc<Workspace>,
    project_key: &ProjectKey,
    label: &str,
    force: bool,
    teardown_wait: Duration,
    respond: Sender<DespawnResult>,
)

handle_despawn_worker with the teardown wait injected, so a case can drive the expiry without sitting out the production budget.