feat(gc): record event type for manifest tasks queued due to list delete

mentioned in commit 23e5781f

mentioned in issue #489 (closed)

mentioned in merge request gitlab-org/build/CNG!826 (merged)

mentioned in merge request gitlab-com/gl-infra/k8s-workloads/gitlab-com!1359 (merged)

mentioned in merge request gitlab-com/gl-infra/k8s-workloads/gitlab-com!1361 (merged)

mentioned in merge request gitlab-org/charts/gitlab!2276 (merged)

mentioned in merge request omnibus-gitlab!5827 (merged)

mentioned in merge request gitlab-development-kit!2385 (merged)