SPIGOT-7362: Properly handle null in CraftBlock#blockFaceToNotch()

By: Parker Hawke <hawkeboyz2@hotmail.com>

paper-server/src/main/java/org/bukkit/craftbukkit/block/CraftBlock.java

@@ -310,6 +310,9 @@ public class CraftBlock implements Block {
     }
 
     public static EnumDirection blockFaceToNotch(BlockFace face) {
+        if (face == null) {
+            return null;
+        }
         switch (face) {
             case DOWN:
                 return EnumDirection.DOWN;