events: unlink stopPropagation and cancelBubble methods

WHATWG spec does not define any explicit relationship between
stopPropagation and cancelBubble, the methods' responsibilities are
simply to "set this’s stop propagation flag"
under varying circumstances.

Fixes: nodejs#50401

lib/internal/event_target.js

@@ -306,7 +306,7 @@ class Event {
     if (!isEvent(this))
       throw new ERR_INVALID_THIS('Event');
     if (value) {
-      this.stopPropagation();
+      this.#propagationStopped = true;
     }
   }