Fix Auto Filler crash (#335)

src/main/java/com/glodblock/github/common/tile/TileFluidAutoFiller.java

@@ -282,9 +282,10 @@ public class TileFluidAutoFiller extends AENetworkInvTile
         if (!initialized) { // run postEvent on AE network is ready
             initialized = true;
             postEvent();
-            if (this.returnStack == null) return TickRateModulation.SLEEP;
         }
 
+        if (this.returnStack == null) return TickRateModulation.SLEEP;
+
         if (this.getStorageGrid() == null) {
             return TickRateModulation.SLOWER;
         }