Update README.md

[poga]

add link to colab notebook

PR checklist

• [x] Ensure you have added or ran the appropriate tests for your PR.
• [x] DCO signed

What type of PR is this?

documentation

What this PR does / why we need it:

link to our SDK demo in Google Colab

Which issue(s) this PR fixes:

Special notes for your reviewer:

Does this PR introduce a user-facing change?:

NONE