Fix AsyncTransport verify_ssl and proxy

[adammillerio]

The conversion to using httpx for AsyncTransport brought with it a few bugs that make it unusable:

• Any proxy or verify_ssl setting provided was not passed to the wsdl_client, meaning that it was more or less impossible to get a useable client if verification needs to be disabled.
• Incorrect keyword arguments were used for verify_ssl (should be verify) and proxy (should be proxies).

This fixes these by passing any verify_ssl or proxy settings into the client constructors, so that they persist across all interactions. In addition, timeout settings were also moved into the client.

[mvantellingen]

Good point! Thanks! Everything else working correctly?

[adammillerio]

@mvantellingen Yup! So far so good with async zeep after fixing this up. I'll keep you posted if I hit anything strange along the way.

Is there any chance you could possibly cut a new prerelease build in PyPI? Right now I am just building the wheel off of my fork for testing, but being able to hit PyPI directly again would be great.

[mvantellingen]

Good to hear, I've just released 4.0.0. Hoping that this (partial) async implementation is easier to maintain :)