fix: temporarily gracefully handle nested lists during imports

mentioned in commit e1110996

mentioned in issue #709 (closed)

mentioned in merge request gitlab-org/build/CNG!1051 (merged)

mentioned in merge request gitlab-com/gl-infra/k8s-workloads/gitlab-com!1851 (merged)

mentioned in merge request gitlab-com/gl-infra/k8s-workloads/gitlab-com!1852 (merged)

mentioned in merge request gitlab-org/charts/gitlab!2616 (merged)

mentioned in merge request omnibus-gitlab!6181 (merged)

mentioned in merge request gitlab-development-kit!2656 (merged)