Fix Docker entrypoint passthrough test

When updating to PHP 8.3 (or Symfony 7.2) the prefix output of `bin/console` changed to `)Symfony` instead of `(Symfony`. For some reason this extra character only appears in this test as far as I'm aware. Simplified with a basic echo command to make the test more consistent.

Author: codedmonkey

tests/Docker/Standalone/EntrypointTest.php

@@ -45,14 +45,14 @@ public function testDirigent(): void
     public function testPassthrough(): void
     {
         $container = (new GenericContainer('dirigent-standalone'))
-            ->withCommand(['--', 'bin/console', 'list'])
-            ->withWait(new WaitForLog('Symfony'))
+            ->withCommand(['--', 'echo', 'i have a dream'])
+            ->withWait(new WaitForLog('dream'))
             ->start();
 
         $result = $container->logs();
 
         $container->stop();
 
-        $this->assertStringStartsWith(')Symfony', $result, 'Running the container with an `--` argument must have its remaining arguments be interpreted as a command.');
+        $this->assertSame('i have a dream', $result, 'Running the container with an `--` argument must have its remaining arguments be interpreted as a command.');
     }
 }