Use array_is_list() function when available

Suggested by Alexander M. Turek <me@derrabus.de> in #4818 (review)

src/Framework/Constraint/Traversable/ArrayIsList.php

@@ -9,6 +9,7 @@
  */
 namespace PHPUnit\Framework\Constraint;
 
+use function array_is_list;
 use function is_array;
 
 /**
@@ -34,6 +35,11 @@ protected function matches(mixed $other): bool
             return false;
         }
 
+        if (function_exists('array_is_list')) {
+            return array_is_list($other);
+        }
+
+        // @todo Remove this code once we require PHP >= 8.1
         if ($other === []) {
             return true;
         }