Add proxy settings for k8s client

[LissaGreense]

Hi!

I added proxy and noproxy settings to k8s client configuration. Both of them are fetched from environment variables.

• [ ] [N/A] At least one example testcase added in testcases/
• [ ] [No changes] Library Documentation regenerated according to Generate docs
• [x] PR entry added in CHANGELOG.md in In progress section
• [ ] [N/A] All new testcases tagged as prerelease along other tags to exclude it from execution until released on PyPI
• [x] Coverage threshold increased in .coveragerc if new coverage is higher than actual, see the lint-and-coverage step in CI

  fail_under = 86

[m-wcislo]

Hi, thanks for the PR, but from what I understand no_proxy is handled in the background see https://github.com/kubernetes-client/python/blob/5a96bbcbe21a552cc1f9cda13e0522fafb0dbac8/kubernetes/client/rest.py#L87 and https://github.com/psf/requests/blob/ac3be98b19f4d09c6a970b271a3ae30f3d0858f7/requests/utils.py#L774. So we don't really need to set it in our code, it will be taken from env vars. Could you verify this?

Also would be great to add small note to the README describing how to handle proxy.

[LissaGreense]

Hi Michal, Thank you for your fast response!

You are totally right! I didn't check this should_bypass_proxies function before. I just noticed that proxy hasn't been set, so I was convinced that no_proxy is also skipped :D

Let me fix this oversight :D

[LissaGreense]

@m-wcislo changes applied, waiting for review ;3

[m-wcislo]

Thanks! merging.