fixup! Put the keys of a list in ascending order and require the ones below a required key

Author: zonuexe

tests/PHPStan/Analyser/nsrt/bug-14177.php

@@ -184,7 +184,7 @@ public function testUnsetNonConstant(array $a, array $b, array $c, int $int): vo
 		unset($c[$int]);
 		assertType('false', array_is_list($a));
 		assertType('bool', array_is_list($b));
-		// the required key 3 makes the keys below it required in a list too
+		// in a list, the required key 3 implies the keys 1 and 2, so unsetting either leaves no list
 		assertType('false', array_is_list($c));
 	}