feat: [confidentialcomputing] add Nvidia Attestation proto message with its relevant fields and ConfidentialGke options#7185

quirogas merged 3 commits intomaingoogleapis/google-cloud-node:mainfrom

owl-bot-copy-packages-google-cloud-confidentialcomputinggoogleapis/google-cloud-node:owl-bot-copy-packages-google-cloud-confidentialcomputingCopy head branch name to clipboard