Don't spawn rad pulses on paused grids (#2121)

* Don't spawn rad pulses on paused grids

* Only radiate default grid

Co-authored-by: Metal Gear Sloth <metalgearsloth@gmail.com>

Content.IntegrationTests/DummyGameTicker.cs

@@ -14,6 +14,9 @@ namespace Content.IntegrationTests
     {
         public GameRunLevel RunLevel { get; } = GameRunLevel.InRound;
 
+        public MapId DefaultMap { get; } = MapId.Nullspace;
+        public GridId DefaultGridId { get; } = GridId.Invalid;
+
         public event Action<GameRunLevelChangedEventArgs> OnRunLevelChanged
         {
             add { }