Enable streaming while respecting proxy settings

[NlightNFotis]

This is for the followup work to what's done in #2599 so that we provide a longer term fix for the issue described in #2593.

In #2599 we opted to deactivate the path that was using streaming, but the longer term, more robust fix, is to use streaming while detecting and respecting proxy settings that the client has setup.

[aeisenberg]

Two options:

1. Correctly apply proxy settings when we do streaming
2. If we detect a proxy, disable streaming

Maybe 2 is a better option because proxies are only going to be set on self-hosted runners, which are more likely to cache the bundle. This means they would not get much benefit from streaming.