prow/plugins/approve/approvers/owners.go
func (ap *Approvers) shouldNotOverrideApproval(login string, noIssue bool) bool {
	login = strings.ToLower(login)
	approval, alreadyApproved := ap.approvers[login]

	return alreadyApproved && approval.NoIssue && !noIssue
}
func (ap *Approvers) shouldNotOverrideApproval(login string, noIssue bool) bool {
	login = strings.ToLower(login)
	approval, alreadyApproved := ap.approvers[login]

	return alreadyApproved && approval.NoIssue && !noIssue
}
// shouldNotOverrideApproval decides whether or not we should keep the
// original approval:
// If someone approves a PR multiple times, we only want to keep the
// latest approval, unless a previous approval was "no-issue", and the
// most recent isn't.