added-buttons-to-public

[ghernandez-57]

Describe your changes added google colab button

Type of update

• Update to documentation

Associated issues

Additional context

For the reviewer See this page for instructions on how to review the pull request.

• [ ] PR functionality reviewed in a Jupyter Notebook
• [ ] All tests pass
• [ ] Test coverage remains 100%
• [ ] Documentation tested
• [ ] New documentation pages added to plantcv/mkdocs.yml
• [ ] Changes to function input/output signatures added to updating.md
• [ ] Code reviewed
• [ ] PR approved