fix: replaced writeHead with socket.write

Author: marco-ippolito

test/parallel/test-domain-multi.js

@@ -46,7 +46,10 @@ const server = http.createServer((req, res) => {
 
   b.on('error', common.mustCall((er) => {
     if (res) {
-      res.writeHead(500);
+      // Introduce an error on the client by writing unexpected data.
+      // The client is now expecting a chunk header so any letter will 
+      // have the parser throw an error.
+      res.socket.write('H');
       res.end('An error occurred');
     }
     // res.writeHead(500), res.destroy, etc.