Seal/abstract/virtual everything (#6739)

Content.Shared/Tabletop/Events/TabletopMoveEvent.cs

@@ -11,7 +11,7 @@ namespace Content.Shared.Tabletop.Events
     /// <see cref="SharedTabletopDraggableComponent"/> has been moved.
     /// </summary>
     [Serializable, NetSerializable]
-    public class TabletopMoveEvent : EntityEventArgs
+    public sealed class TabletopMoveEvent : EntityEventArgs
     {
         /// <summary>
         /// The UID of the entity being moved.

Content.Shared/Tabletop/Events/TabletopPlayEvent.cs

@@ -9,7 +9,7 @@ namespace Content.Shared.Tabletop.Events
     /// An event sent by the server to the client to tell the client to open a tabletop game window.
     /// </summary>
     [Serializable, NetSerializable]
-    public class TabletopPlayEvent : EntityEventArgs
+    public sealed class TabletopPlayEvent : EntityEventArgs
     {
         public EntityUid TableUid;
         public EntityUid CameraUid;

Content.Shared/Tabletop/Events/TabletopStopPlayingEvent.cs

@@ -8,7 +8,7 @@ namespace Content.Shared.Tabletop.Events
     /// An event ot tell the server that we have stopped playing this tabletop game.
     /// </summary>
     [Serializable, NetSerializable]
-    public class TabletopStopPlayingEvent : EntityEventArgs
+    public sealed class TabletopStopPlayingEvent : EntityEventArgs
     {
         /// <summary>
         /// The entity UID of the table associated with this tabletop game.