[cherrypick-0.18] move manifest image references to ghcr (#2529)#2535

google-oss-prow[bot] merged 2 commits intokubeflow:release-0.18kubeflow/katib:release-0.18from

saileshd1402:cherry-pick-db4b68bfsaileshd1402/katib:cherry-pick-db4b68bfCopy head branch name to clipboard