Allow passing own `aiohttp.AsyncClient` to python `RestClientObject`

[abhiaagarwal]

Checklist

• I agree to the terms within the OpenFGA Code of Conduct.

Describe the problem you'd like to have solved

The python-sdk currently instantiates its own RESTClientObject, which in turn initializes a aiohttp.TCPConnection and ClientSession. It's common in webapps to have a global copy of aiohttp to benefit from dns, connection pooling etc, but the python SDK currently does not expose an easy way to override that.

Describe the ideal solution

Allow setting own client through ClientConfiguration.

Alternatives and current workarounds

No response

References

No response

Additional context

Can open a MR!