Add getting started jupyter notebooks

[korikuzma]

Feature description

It would be nice to have jupyter notebooks demonstrating how to use the VA-Spec Pydantic models, similar to VRS-Python (https://github.com/ga4gh/vrs-python/tree/main/notebooks/getting_started)

Use case

This would be helpful for new users + non-technical users

Proposed solution

No response

Alternatives considered

No response

Implementation details

• Provide two options for setup: Python virtual environment + VS Code Dev Containers
• Maybe add MyBinder?

Potential Impact

No response

Additional context

No response

Contribution

None

[korikuzma]

@larrybabb and I were thinking of just copying the test fixtures we have:

1. AAC 2017
2. ACMG 2015
3. CCV
4. CAF

Give examples of how to create these objects + show validation