Fix spawning code-server within code-server (#4590)

* Remove extra VS Code CLI spawn

We already spawn VS Code's CLI when necessary in the lines below.
Having the CLI spawn unconditionally when in a VS Code environment makes
it impossible to run code-server within code-server (for example to
develop it).

* Update VS Code

This sanitizes our environment variables so code-server does not always
think it is a child spawn.

Fixes https://github.com/cdr/code-server/issues/4519.

src/node/entry.ts

@@ -1,32 +1,13 @@
 import { logger } from "@coder/logger"
 import { optionDescriptions, parse, readConfigFile, setDefaults, shouldOpenInExistingInstance } from "./cli"
-import { commit, pkgName, version } from "./constants"
+import { commit, version } from "./constants"
 import { openInExistingInstance, runCodeServer, runVsCodeCli, shouldSpawnCliProcess } from "./main"
 import { monkeyPatchProxyProtocols } from "./proxy_agent"
-import { loadAMDModule } from "./util"
 import { isChild, wrapper } from "./wrapper"
 
-const cliPipe = process.env["VSCODE_IPC_HOOK_CLI"] as string
-const cliCommand = process.env["VSCODE_CLIENT_COMMAND"] as string
-
 async function entry(): Promise<void> {
   monkeyPatchProxyProtocols()
 
-  if (cliPipe || cliCommand) {
-    const remoteAgentMain = await loadAMDModule<CodeServerLib.RemoteCLIMain>("vs/server/remoteCli", "main")
-
-    remoteAgentMain(
-      {
-        productName: pkgName,
-        version,
-        commit,
-        executableName: pkgName,
-      },
-      process.argv.slice(2),
-    )
-    return
-  }
-
   // 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