[Cosmos] Thin client PoC for Python

[TheovanKraay]

Is your feature request related to a problem? Please describe.
Lack of http2 support means large number of connections at scale

Describe the solution you'd like
Implement http2 support to allow for multiplexing

[annatisch]

Thanks @TheovanKraay
To clarify, when you say a large number of connections, is this within a single client? Or because there will be many clients running together?
Would customizing the transport to limit the connection pool size, or sharing it between multiple clients help mitigate the number of connections in the meantime while http2 support is being investigated?

[kushagraThapar]

@annatisch, the thin client prototyping is in regard to various problems including the http connection pool size in all our SDKs, which currently is high because of the throughput expectations of customers. Http2 work will definitely help here, however, for the longer term, thin client will help us to be more consistent in all SDKs across different feature set.