Release the latest connection before accept new one

Author: twose

src/core/Coroutine/Server.php

@@ -111,6 +111,7 @@ public function start(): bool
 
         while ($this->running) {
             /** @var Socket $conn */
+            $conn = null;
             $conn = $socket->accept();
             if ($conn) {
                 $conn->setProtocol($this->setting);