String could not be parse as XML at src/Request.php:137

Some responses from UPS contain and encoded single quote `&#26;` which causes a failure here "gabrielbull/ups-api/src/Request.php:137". The convertEncoding method doesn't fix the issue.

Context:

```
<ReasonDescription>
    WE WERE UNABLE TO DELIVER YOUR PACKAGE. IT&#26;S ON THE WAY TO A SECURE UPS ACCESS POINT LOCATION FOR PICK UP.
</ReasonDescription>