failed to set multiple wordforms

not quite sure how to set multiple wordform files for index
```php
$params = [
'body' => [
'settings' => [
'wordforms' => '/usr/local/sphinx/data/wordforms.txt'
],
'columns' => [
'title'=>['type'=>'text'],
'price'=>['type'=>'float']
]
],
'index' => 'products'
];
$index = new \Manticoresearch\Index($client);
$index->create($params);
```

however index with such config works well
```
index products {
wordforms = /usr/local/sphinx/data/wordforms.txt
wordforms = /usr/local/sphinx/data/alternateforms.txt

type = rt
path = idx
rt_field = title
rt_attr_uint = price
}
```