fix: remove listener from correct object (#1768)

Author: wuhkuh

.changeset/windmills-can-fly.md

@@ -0,0 +1,5 @@
+---
+'livekit-client': patch
+---
+
+Fix leaking memory by removing event listener from correct scope

src/room/Room.ts

@@ -937,7 +937,7 @@ class Room extends (EventEmitter as new () => TypedEmitter<RoomEventCallbacks>)
       window.addEventListener('beforeunload', this.onPageLeave);
     }
     if (isWeb()) {
-      document.addEventListener('freeze', this.onPageLeave);
+      window.addEventListener('freeze', this.onPageLeave);
     }
     this.setAndEmitConnectionState(ConnectionState.Connected);
     this.emit(RoomEvent.Connected);