Retry on paper load failures

src/main/java/com/volmit/iris/core/pregenerator/methods/AsyncPregenMethod.java

@@ -63,7 +63,8 @@ public class AsyncPregenMethod implements PregeneratorMethod {
             PaperLib.getChunkAtAsync(world, x, z, true).get();
             listener.onChunkGenerated(x, z);
         } catch (Throwable e) {
-            e.printStackTrace();
+            J.sleep(5);
+            future.add(burst.complete(() -> completeChunk(x, z, listener)));
         }
     }