[Feature] implement trust_env

[rknyip]

Is your feature request related to a problem? Please describe.
It seems that requests.Session(trust_env=False) is not implemented, from my test and your code. I suppose it is possible cuz --noproxy can be provided to curl command.

Describe the solution you'd like
Grateful for implementing it.

Describe alternatives you've considered
unset and recover os.environ which causes inconvenience.

Additional context
Nope.

[perkfly]

It's more than setting CURLOPT_NOPROXY, since this option does not only override http_proxy, but also override the proxy you specified inside the program.

(lib)curl always checks environment variables, to fix this, we have to dig into and patch the C code again. It will take a while.

[perkfly]

If you don't want any proxies, you can simply set curl_options={CurlOpt.NOPROXY: "*"}.