Openapi 3.0.0 spec and Python Client with magic syntax support

[yababer]

For our use case, it made sense to create an openapi 3.0.0 spec to autogenerate a typescript client. This spec is based on the current rest interface.

We would like to contribute back to the community for others.

[yababer]

As an update, we create an open-source python client to submit flink sql jobs. This client also has support jupyter magic syntax:

https://gitlab.com/belvederetrading/public/flink_sql_python_client