test: add test for socket.end callback

PR-URL: https://github.com/nodejs/node/pull/24087
Refs: https://github.com/nodejs/node/pull/23937
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>

test/parallel/test-net-socket-end-callback.js

@@ -0,0 +1,22 @@
+'use strict';
+
+const common = require('../common');
+const net = require('net');
+
+const server = net.createServer((socket) => {
+  socket.resume();
+}).unref();
+
+server.listen(common.mustCall(() => {
+  const connect = (...args) => {
+    const socket = net.createConnection(server.address().port, () => {
+      socket.end(...args);
+    });
+  };
+
+  const cb = common.mustCall(() => {}, 3);
+
+  connect(cb);
+  connect('foo', cb);
+  connect('foo', 'utf8', cb);
+}));