[Feature] Support ApiVersion.API_VERSION_CODE updating

[tomyeunghb]

Currently ApiVersion.API_VERSION_CODE hardcoded to "2020-03-02".
Do we have any function to update api version code when we init the Stripe instance?

[tianzhao-stripe]

Hi @tomyeunghb

Thank you for the suggestion! We revisit our roadmap periodically and will keep this idea in mind.

Is there specific functionality that you think is missing or that you need for your own use case that would be solved by using newer versions of the Stripe API?