fix: Drastically reduce number of display lists when transporting fluids (#45)

LogisticsNewPipeItemBoxRenderer has a display list cache for rendering
fluids. Unfortunately there is a small bug/typo where a `FluidStack`
is used as the key for lookup, but a `FluidIdentifier` is used for
writing the cached display list array.

Essentially, the cache is unused and we create a fresh display list
for every traveling liquid box in every frame.

To fix, we simply use the FluidIdentifier consistently. This should
help with FPS in networks with lots of (vsibily) traveling fluids.

(cherry picked from commit 3848737)

Author: szuend

src/main/java/logisticspipes/renderer/newpipe/LogisticsNewPipeItemBoxRenderer.java

@@ -71,12 +71,8 @@ public void doRenderItem(ItemIdentifierStack itemIdentifierStack, float light, d
     }
 
     private int getRenderListFor(FluidStack fluid) {
-        FluidIdentifier ident = FluidIdentifier.get(fluid);
-        int[] array = LogisticsNewPipeItemBoxRenderer.renderLists.get(fluid);
-        if (array == null) {
-            array = new int[LogisticsNewPipeItemBoxRenderer.RENDER_SIZE];
-            LogisticsNewPipeItemBoxRenderer.renderLists.put(ident, array);
-        }
+        int[] array = LogisticsNewPipeItemBoxRenderer.renderLists
+                .computeIfAbsent(FluidIdentifier.get(fluid), k -> new int[LogisticsNewPipeItemBoxRenderer.RENDER_SIZE]);
         int pos = Math.min(
                 (int) (((Math.min(fluid.amount, 5000) * 1.0F) * LogisticsNewPipeItemBoxRenderer.RENDER_SIZE) / 5000),
                 LogisticsNewPipeItemBoxRenderer.RENDER_SIZE - 1);