Expose a way to configure request timeout

[abe-101]

The python requests library supports adding a timeout to requests(docs - source code). Would it be possible to expose a way to configure the gocardless-pro-python client (or individual requests) to set a value for that timeout?

I'm opening this issue to ask if you are open to such a contribution, or if there’s already a way to do this that I’ve missed. Let me know if this is something you’d consider, and if you have any preferences for how it should be implemented.

Thanks!