qa: ensure array_merge has at least one argument

Signed-off-by: Maximilian Bösing <2189546+boesing@users.noreply.github.com>

src/Psalm/Internal/Codebase/ClassConstantByWildcardResolver.php

@@ -55,6 +55,6 @@ public function resolve(string $class_name, string $constant_pattern): ?array
             $matched_class_constant_types[] = $class_constant_storage->type->getAtomicTypes();
         }
 
-        return array_values(array_merge(...$matched_class_constant_types));
+        return array_values(array_merge([], ...$matched_class_constant_types));
     }
 }