[DeadCode] Skip RecastingRemovalRector on array dim fetch value

[TomasVotruba]

Array dim fetch values can hold anything at runtime. PHPStan often reports a narrow type (e.g. int[]) where the real type is mixed[], so removing the cast changes behavior.

 $list = ['id' => 1, 'name' => 'Tom'];

-$id = (int) $list['id'];
-$name = (string) $list['name'];
+$id = $list['id'];
+$name = $list['name'];

Now skipped.