Remove utf8_encode() function

[krzysztofrewak]

With PHP8.2 utf8_encode function will be deprecated (source). I refactored:

utf8_encode($text)

to:

mb_convert_encoding($text, 'UTF-8', mb_list_encodings())

to avoid problems with newer PHP versions.

[wojtekmieszczak]

@jasonvarga note that it won't work using PHP 8.1.0 - php/php-src#7898

[jasonvarga]

Great.

It's fixed in 8.1.2, at least.