Updated required owned elms rule description (#2305)

* Updated required owned elms rule description

* Update _rules/aria-required-owned-element-bc4a75.md

Co-authored-by: Dan Tripp <113939352+dan-tripp-siteimprove@users.noreply.github.com>

---------

Co-authored-by: Dan Tripp <113939352+dan-tripp-siteimprove@users.noreply.github.com>

Author: WilcoFiers

_rules/aria-required-owned-element-bc4a75.md

@@ -4,7 +4,7 @@ name: ARIA required owned elements
 rules_format: 1.1
 rule_type: atomic
 description: |
-  This rule checks that an element with an explicit semantic role has at least one of its required owned elements.
+  This rule checks that an element with an explicit role that restricts which elements it can own only owns such elements.
 accessibility_requirements:
   wcag20:1.3.1: # Info and Relationships (A)
     forConformance: true