Changes the Python SDK connection timeout to 60s

[wvandeun]

Change the connection timeout for the Python SDK to 60s.

This is mainly to resolve some issue we see with implementations that implement large datasets on:

failing to start the Infrahub CI pipeline
requests in large batches of concurrent mutations timing out
request to retrieve generator group with large amount of members timing out

This should be revisited as soon as we have more through solutions for the above.

opsmill/infrahub-sdk-python#69