fix NPE on EntityTeleportEvent getTo (#10016)

patches/server/Fix-missing-event-call-for-entity-teleport-API.patch

@@ -17,7 +17,7 @@ index 0000000000000000000000000000000000000000..00000000000000000000000000000000
 +            this, this.getLocation(), location);
 +        // cancelling the event is handled differently for players and entities,
 +        // entities just stop teleporting, players will still teleport to the "from" location of the event
-+        if (!event.callEvent()) {
++        if (!event.callEvent() || event.getTo() == null) {
 +            return false;
 +        }
 +        location = event.getTo();