fix: infinite proxy loop (#4676)

I think the problem is that when a proxy is not in use proxy-agent
returns the global agent...which is itself since we set it globally,
causing the loop.

VS Code already covers proxies meaning we only need to do it in our own
requests so to fix this pass in the agent in the version fetch request
instead of overidding globally.

Also avoid proxy-from-env and pass in the proxy URI instead as both
http_proxy and https_proxy can be used for either http or https requests
but it does not allow that.

src/node/entry.ts

@@ -2,12 +2,9 @@ import { logger } from "@coder/logger"
 import { optionDescriptions, parse, readConfigFile, setDefaults, shouldOpenInExistingInstance } from "./cli"
 import { commit, version } from "./constants"
 import { openInExistingInstance, runCodeServer, runVsCodeCli, shouldSpawnCliProcess } from "./main"
-import { monkeyPatchProxyProtocols } from "./proxy_agent"
 import { isChild, wrapper } from "./wrapper"
 
 async function entry(): Promise<void> {
-  monkeyPatchProxyProtocols()
-
   // There's no need to check flags like --help or to spawn in an existing
   // instance for the child process because these would have already happened in
   // the parent and the child wouldn't have been spawned. We also get the