fix bug in register_event method

Author: MaxDall

src/fundus/utils/events.py

@@ -163,7 +163,7 @@ def register_event(self, event: str, key: Union[int, str, None] = None):
         with self._lock:
             if isinstance(key, str) and key not in self._aliases:
                 self._alias(key)
-            if (resolved := self._resolve(key)) not in self._events:
+            if event not in self._events[(resolved := self._resolve(key))]:
                 self._events[resolved][event] = threading.Event()
                 logger.debug(f"Registered event {event!r} for {self._pretty_resolve(key)}")