[Tracking Issue] Update contents to kubeflow v1.5

[yhwang]

Since Kubeflow v1.5 is out in April 2022, we'd like to update the content to use it. Use this issue to trace the overall progress.

• [x] Kubeflow Deployment
• [x] Kubeflow Pipelines with Tekton
• [ ] Examples, including python examples and notebooks
• [ ] KFServing to KServe

[yhwang]

• updated kubeflow deployment on #99
• updated kfp-tekton on #100

[yhwang]

update day-1 handson: #103