Truthy check fails to refine type

```php
$s = rand(0, 1) ? 0 : 1;

if ($s) {
  $s = 3;
}

if ($s === 1) {}
```

Expected: Strict comparison using === between 0|3 and 1 will always evaluate to false.
Actual: [No issue](https://phpstan.org/r/cfb55fffcef59e4c9b4cd344e73060ff)

Fixed by making the comparison explicit:

```php
$s = rand(0, 1) ? 0 : 1;

if ($s === 1) {
  $s = 3;
}

if ($s === 1) {}
```