Fix SimAntics unit test

Author: ammaraskar

Assets/Scripts/OpenTS2/SimAntics/VM.cs

@@ -74,6 +74,11 @@ public void Tick()
                 }
                 catch(Exception e)
                 {
+                    // If we don't have an exception handler just re-throw to avoid swallowing errors.
+                    if (ExceptionHandler == null)
+                    {
+                        throw;
+                    }
                     ExceptionHandler?.Invoke(e, entity);
                 }
             }

Assets/Scripts/OpenTS2/SimAntics/VMEntity.cs

@@ -113,12 +113,14 @@ public void Delete()
         public BHAVAsset GetBHAV(ushort treeID)
         {
             // 0x0XXX is global scope, 0x1XXX is private scope and 0x2XXX is semiglobal scope.
-            var groupid = SemiGlobalGroupID;
+            uint groupid;
 
             if (treeID < 0x1000)
                 groupid = GroupIDs.Global;
             else if (treeID < 0x2000)
                 groupid = PrivateGroupID;
+            else
+                groupid = SemiGlobalGroupID;
 
             return VM.GetBHAV(treeID, groupid);
         }