Swap out requests to avoid LGPL dependency

[ashb]

This library depends upon requests, and while requests itself is Apache 2 licensed, it depends upon chardet which is LGPL'd.

This leads to confusing licensing situations for projects using this python docker client, and it is the view of the Apache Software Foundation that any LGPL dep places some restrictions on the downstream projects, and thus has to be avoided.

See psf/requests#5797 for the latest attempt to change the dependency upstream (which at the time of writing appears to be a Wont Fix, so I closed the PR)

So: I would like to propose that requests is switched out to httpx library -- it is broadly API compatible with requests.

I am happy to attempt this PR, but first I wanted to raise the issue and see if a PR will be accepted!

[feliperuhland]

That would be nice!

[ashb]

Requests no longer pulls in a LGPL'd module, so we can close this.