Infinity reading

[Anthonybelui]

Hello, thanks for developing the library.
I wanted to ask you to fix/define the logic for the read timeout in socks_proxy. This creates an infinity reading.

File httpcore/_sync/socks_proxy.py
Function _init_socks5_connection()
Line: incoming_bytes = stream.read(max_bytes=4096) > incoming_bytes = stream.read(max_bytes=4096, timeout=SomeTimeout)

[tomchristie]

Well spotted yea.
You could escalate this into an issue if you like... "Socks proxy should support read/write timeouts".

A pull request for this would be ace.