Unmark ::details-content as partial in Safari (#28182)

This omission does not have demonstrable negative impact on web developers.

Author: caugner

css/selectors/details-content.json

@@ -24,9 +24,7 @@
             "opera_android": "mirror",
             "safari": {
               "version_added": "18.4",
-              "impl_url": "https://webkit.org/b/283446",
-              "partial_implementation": true,
-              "notes": "Does not support chaining pseudo-elements after `::details-content`."
+              "notes": "Does not support chaining pseudo-elements after `::details-content`. See [bug 283446](https://webkit.org/b/283446)."
             },
             "safari_ios": "mirror",
             "samsunginternet_android": "mirror",