[enh] migrate check_port_is_open to asyncio

yunodiagnoser.py

@@ -289,14 +289,23 @@ async def check_ports(request):
 async def check_port_is_open(ip, port):
 
     if ":" in ip:
-        sock = socket.socket(socket.AF_INET6, socket.SOCK_STREAM)
+        futur = asyncio.open_connection(ip, port, family=socket.AF_INET6)
     else:
-        sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
-    sock.settimeout(2)
-    result = sock.connect_ex((ip, port))
-    sock.close()
-    return result == 0
+        futur = asyncio.open_connection(ip, port, family=socket.AF_INET)
 
+    try:
+        _, writer = await asyncio.wait_for(futur, timeout=2)
+    except (asyncio.TimeoutError, ConnectionRefusedError):
+        return False
+    except Exception:
+        import traceback
+        traceback.print_exc()
+        return False
+    else:
+        writer.close()
+        await writer.wait_closed()
+
+        return True
 
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