Can not send email because of failing mb_encode_mimeheader

[blummarci24]

Issue

There is a failing code in the legacy Localization.php in translateCharsetMIME function causing error on email sending.

The failing code is here:

$result = mb_encode_mimeheader($string, $toCharset, $encoding);

Digging deeper it is a change in polyfill-mbstring dependency:

```public static function mb_encode_mimeheader($s, $charset = null, $transferEncoding = null, $linefeed = null, $indent = null)
{
    trigger_error('mb_encode_mimeheader() is bugged. Please use iconv_mime_encode() instead', \E_USER_WARNING);
}```

Possible Fix

As suggested, use iconv_mime_encode. I have a working local solution for this which fix this issue.

    public function translateCharsetMIME($string, $fromCharset, $toCharset = 'UTF-8', $encoding = "Q")
    {
        $preferences = array(
            'input-charset' => $fromCharset,
            'output-charset' => $toCharset,
            'line-length' => 76,
            'scheme' => $encoding,
            'line-break-chars' => "\n"
        );
        $result = iconv_mime_encode('', $string, $preferences);
        return substr($result, 2);
    }
    
    ```
    
    I will create a PR for this.

### Steps to Reproduce the Issue

```bash
1. Set up an new suitecrm environment (tested on 8.7 and php 8.2)
2. Login and go to admin page
3. Configure email and try to send a test email
...

Context

I tried the email functionality. I have not found any other topic to this certain issue, so I took a look at the code.

Version

8.7.0

What browser are you currently using?

Chrome

Browser Version

No response

Environment Information

PHP 8.2

Operating System and Version

Ubuntu 20.04.6 LTS

[blummarci24]

Fix in:

#568