http: remove duplicate check

`socketOnDrain()` performs the exact same check and doesn't return
anything.

PR-URL: #29022
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Trivikram Kamat <trivikr.dev@gmail.com>
Reviewed-By: Rich Trott <rtrott@gmail.com>

lib/_http_server.js

@@ -444,13 +444,9 @@ function connectionListenerInternal(server, socket) {
   socket._paused = false;
 }
 
-
 function updateOutgoingData(socket, state, delta) {
   state.outgoingData += delta;
-  if (socket._paused &&
-      state.outgoingData < socket.writableHighWaterMark) {
-    return socketOnDrain(socket, state);
-  }
+  socketOnDrain(socket, state);
 }
 
 function socketOnDrain(socket, state) {