Check for existence of GitRepository.Spec.Reference when displaying a trace to avoid error: ✗ template: tmpl:28:21: executing "tmpl" at <.GitRepository.Spec.Reference.Tag>: nil pointer evaluating *v1beta1.GitRepositoryRef.Tag Fixes issue #1621 Manually tested using the use cases highlighted in the issue. Signed-off-by: Allen Porter <allen@thebends.org>