Refactor ghost boo to ECS (#4511)

* Moved ghost boo to ecs

* Fixed small light exception

* No need to inject EM

* Moved cooldown and time to fields

Co-authored-by: metalgearsloth <31366439+metalgearsloth@users.noreply.github.com>

Content.Server/Ghost/GhostBooEvent.cs

@@ -0,0 +1,9 @@
+using Robust.Shared.GameObjects;
+
+namespace Content.Server.Ghost
+{
+    public class GhostBooEvent : HandledEntityEventArgs
+    {
+
+    }
+}