Remove proxy setting in steps.py since it is no longer needed.
rdar://80175609
Created attachment 433070 [details] Patch
Proxy servers will be configured as environment variables on worker nodes.
Committed r279676 (239481@main): <https://commits.webkit.org/239481@main> All reviewed patches have been landed. Closing bug and clearing flags on attachment 433070 [details].
Restarted buildbot to pick up this change