Correct use of corporate proxy

[LioRei]

What kind of issue is this?

• PlatformIO Core.
  If you’ve found a bug, please provide an information below.

You can erase any parts of this template not applicable to your Issue.

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Configuration

Operating system: Windows

PlatformIO Version (platformio --version): PlatformIO Core, version 6.1.4

Description of problem

Platformio is not able to correctly install behind a corporate proxy. HTTPClient and FileDownloader isn't reading env variable to see if there is a proxy or not so the download of platformio/contrib-piohome is not possible.

Steps to Reproduce

1. have a computer behing a corporate proxy
2. install platformio
3. try to do a "pio home"

Actual Results

Error in download of the package

Expected Results

No error

Additional info

I've modified the python script on my computer and I will link a draft PR with my change

[LioRei]

draft PR: #4433

[ivankravets]

Could you re-test with pio upgrade --dev? See newly added docs on how to configure the proxy https://docs.platformio.org/en/latest/core/installation/proxy-configuration.html