true if an array contains another array.
arrInside($array)
$array: array to be checked
vdump(arrInside([1, 2, 3])); //false
vdump(arrInside([1 => 'name'])); //false
vdump(arrInside([[]])); //true
vdump(arrInside([1, 2, 'name' => ['foo', 'bar'])); //true