Add notebook sample CI testing template from synthtool

[loferris]

In which file did you encounter the issue?

This requires adding two files at project root: owlbot.py and repo-metadata.json

Did you change the file? If so, how?

Two new files are added

Describe the issue

Currently, notebooks in this repo do not have CI testing. In order to import testing pipeline files from synthtool, this repo must be configured to subscribe to owlbot updates.