Update CKEditorHelper.php

Adding a fix language method due a incompatibility between translation tags used in CKEditor and Symfony. For example: symfony uses ``pt_BR`` to Brazilian Portuguese and CKeditor uses ``pt-br`` other languages as ``zh_CN`` will be positive affected too.
IMO, we should update the `renderReplace` method to avoid having to reset the json builder here. Can you please use something like:

``` php
$config = $this->fixConfigLanguage($config);
$config = $this->fixConfigContentsCss($config);
$config = $this->fixConfigFilebrowsers($config);

$this->jsonBuilder
    ->reset()
    ->setValues($config);
 
$this->fixConfigEscapedValues($config);
 
return sprintf('CKEDITOR.replace("%s", %s);', $id, $this->fixConfigConstants($this->jsonBuilder->build()));
```