#253 magic quotes are deprecated in PHP 7.4, removed in PHP 8.0, causing showstopping errors

extlib/HTTP/Request2.php uses both get_ and set_magic_quotes_runtime() causing "Internal Server Error" because of a call to an undefined function. It is handled well in vendor/ezyang/htmlpurifier/library/HTMLPurifier/Config.php with a function_exists() check. Source of deprecation/removal info: https://www.php.net/manual/en/function.get-magic-quotes-runtime.php https://www.php.net/manual/en/function.get-magic-quotes-gpc.php