fix: prevent EventListenersTest setup/teardown errors in CI

Added setUp() check for REDIS_AVAILABLE environment variable to skip
entire test class before Laravel's HandleExceptions tries to flush state.

This prevents the TypeError:
  PHPUnit\Runner\ErrorHandler::enable(): Argument #1 must be of type
  PHPUnit\Framework\TestCase, null given

The error occurred in prefer-lowest CI runs where Laravel's error handler
state management conflicted with PHPUnit's TestCase initialization.

Now the test class is skipped entirely in non-Redis environments,
preventing any setup/teardown code from running.

Author: sylvesterdamgaard

tests/Feature/EventListenersTest.php

@@ -18,6 +18,16 @@ final class EventListenersTest extends TestCase
 {
     use RefreshDatabase;
 
+    protected function setUp(): void
+    {
+        // Skip entire test class if Redis is not available
+        if (! getenv('REDIS_AVAILABLE')) {
+            $this->markTestSkipped('Requires Redis - run with redis group');
+        }
+
+        parent::setUp();
+    }
+
     protected function getPackageProviders($app): array
     {
         return [