Fixed Room.Blackout not turning off lights (#2319)

Co-authored-by: Yamato <66829532+louis1706@users.noreply.github.com>
Co-authored-by: Misaka-ZeroTwo <45165615+Misaka-ZeroTwo@users.noreply.github.com>

Exiled.API/Features/Room.cs

@@ -310,9 +310,19 @@ public static Room FindParentRoom(GameObject objectInRoom)
         /// <summary>
         /// Flickers the room's lights off for a duration.
         /// </summary>
-        /// <param name="duration">Duration in seconds.</param>
-        public void TurnOffLights(float duration)
+        /// <param name="duration">Duration in seconds, or -1 for an indefinite duration.</param>
+        public void TurnOffLights(float duration = -1)
         {
+            if (duration == -1)
+            {
+                foreach (RoomLightController light in RoomLightControllers)
+                {
+                    light.SetLights(false);
+                }
+
+                return;
+            }
+
             foreach (RoomLightController light in RoomLightControllers)
             {
                 light.ServerFlickerLights(duration);