document compatibility workarounds

tests/DatabaseTestCase.php

@@ -28,9 +28,11 @@ abstract class DatabaseTestCase extends TestCase
 
     public function artisan($command, $parameters = [])
     {
-        // Laravel 5.6's Kernel::call uses a numeric command key, which the
+        // TODO(compat): Laravel 5.6's Kernel::call uses a numeric command key, which the
         // locked Symfony Console reads as a string offset on PHP 7.4.
-        // Use its normal input handler with a named command until upgraded.
+        // After upgrading Laravel/Symfony, remove this entire override and its
+        // Kernel, ArrayInput and BufferedOutput imports once `just test` passes
+        // using Laravel's inherited artisan() helper.
         $output = new BufferedOutput;
         $status = $this->app[Kernel::class]->handle(
             new ArrayInput(array_merge(['command' => $command], $parameters)), $output