use FixedPortGenerator for legacy implementations

tests/Integration/OldTests/ContainerTest.php

@@ -17,13 +17,6 @@ use Testcontainers\Container\RedisContainer;
  */
 class ContainerTest extends TestCase
 {
-    //TODO: remove after check
-    //To make it work, fixed port should be first implemented
-    protected function setUp(): void
-    {
-        $this->markTestIncomplete();
-    }
-
     public function testMySQL(): void
     {
         $container = MySQLContainer::make();