Fix deprecation of dynamic properties (#16440)

* Fix deprecation of dynamic properties

Define magic method __set and __get in the class to avoid the deprecation message. See: https://php.watch/versions/8.2/dynamic-properties-deprecated#__get-__set

* Fix 'Cannot assign by reference to overloaded object'

* Use AllowDynamicProperties attribute instead of __get()/__set()

---------

Co-authored-by: Jason Coward <jason@opengeek.com>

core/src/Revolution/Hashing/modHashing.php

@@ -19,6 +19,7 @@
  *
  * @package MODX\Revolution\Hashing
  */
+#[\AllowDynamicProperties]
 class modHashing
 {
     /**
@@ -104,7 +105,7 @@ public function getHash($key, $class, $options = [])
                 $hash = new $className($this, $options);
                 if ($hash instanceof $className) {
                     $this->_hashes[$key] = $hash;
-                    $this->$key =& $this->_hashes[$key];
+                    $this->$key = $this->_hashes[$key];
                 }
             }
             if (array_key_exists($key, $this->_hashes)) {