fix(datastore): do not ignore last tag lookup error when importing tags

mentioned in commit 88d23966

mentioned in merge request gitlab-org/build/CNG!1011 (merged)

mentioned in issue #675 (closed)

mentioned in merge request gitlab-com/gl-infra/k8s-workloads/gitlab-com!1760 (merged)

mentioned in merge request gitlab-com/gl-infra/k8s-workloads/gitlab-com!1761 (merged)

mentioned in merge request gitlab-org/charts/gitlab!2557 (merged)

mentioned in commit 535492d5

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

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