Replace str_split with preg_split to properly handle multibyte characters 

SequenceMatcher.php : 138

```php
if (!is_array($version1)) {
    $version1 = str_split($version1);
}
```

```php
if (!is_array($version1)) {
    $version1 = preg_split("//u", $a);
}
```

See here for details
https://www.php.net/manual/en/function.preg-split.php#124158