Update link to ACM+GitLab paper
Update link to ACM+GitLab paper

Change-Id: I8d470caf2e9703ccdc15ff6bd118e840f536836d

GoogleCloudPlatform/solutions-modern-cicd-anthos,GoogleCloudPlatform/solutions-modern-cicd-anthos,GoogleCloudPlatform/solutions-modern-cicd-anthos