Fix biomedata on some custom Spigot versions

common/src/main/java/us/myles/ViaVersion/protocols/protocol1_15to1_14_4/packets/WorldPackets.java

@@ -101,6 +101,7 @@ public class WorldPackets {
                         if (chunk.isGroundUp()) {
                             int[] biomeData = chunk.getBiomeData();
                             int[] newBiomeData = new int[1024];
+                            if (biomeData != null) {
                                 // Now in 4x4x4 areas - take the biome of each "middle"
                                 for (int i = 0; i < 4; ++i) {
                                     for (int j = 0; j < 4; ++j) {
@@ -114,6 +115,7 @@ public class WorldPackets {
                                 for (int i = 1; i < 64; ++i) {
                                     System.arraycopy(newBiomeData, 0, newBiomeData, i * 16, 16);
                                 }
+                            }
 
                             chunk.setBiomeData(newBiomeData);
                         }