modify default connect constructor

Author: hotdang-ca

lib/src/mysql_client/connection.dart

@@ -70,16 +70,20 @@ class MySQLConnection {
   /// SET @@collation_connection=$_collation, @@character_set_client=utf8, @@character_set_connection=utf8, @@character_set_results=utf8
   /// ```
   static Future<MySQLConnection> createConnection({
-    required String host,
+    required dynamic host,
     required int port,
     required String userName,
     required String password,
     bool secure = true,
     String? databaseName,
     String collation = 'utf8_general_ci',
   }) async {
-    final socket = await Socket.connect(host, port);
-    socket.setOption(SocketOption.tcpNoDelay, true);
+    final Socket socket = await Socket.connect(host, port);
+
+    if (socket.address.type != InternetAddressType.unix) {
+      // no support for extensions on sockets
+      socket.setOption(SocketOption.tcpNoDelay, true);
+    }
 
     final client = MySQLConnection._(
       socket: socket,