tests: add pipeline serialization test case

Author: 090809

src/Instrumentation/Laravel/tests/Unit/Watches/RedisCommand/SerializerTest.php

@@ -34,5 +34,7 @@ public function serializeCases(): iterable
 
         // Parameters of array type
         yield ['EVAL', ['param1', 'param2', ['arg1', 'arg2']], 'EVAL param1 param2 ["arg1","arg2"]'];
+
+        yield ['pipeline', [function () {}], 'pipeline Callable'];
     }
 }