Fix sign lazy initialisation

Fixes PaperMC/Paper#4975

Spigot-Server-Patches/0178-API-to-get-a-BlockState-without-a-snapshot.patch

@@ -130,23 +130,6 @@ index 26cc40e57f5b73b9c32859bff37c4a3d94904c56..feeae1a9eb309ae4101783b191bb2bff
      }
  
      private T createSnapshot(T tileEntity) {
-diff --git a/src/main/java/org/bukkit/craftbukkit/block/CraftSign.java b/src/main/java/org/bukkit/craftbukkit/block/CraftSign.java
-index 81f6bf5533288ed90e2f1f4d421d54195d9650c7..4a266b95afea5c3853774752f94e287234fa5726 100644
---- a/src/main/java/org/bukkit/craftbukkit/block/CraftSign.java
-+++ b/src/main/java/org/bukkit/craftbukkit/block/CraftSign.java
-@@ -18,10 +18,12 @@ public class CraftSign extends CraftBlockEntityState<TileEntitySign> implements
- 
-     public CraftSign(final Block block) {
-         super(block, TileEntitySign.class);
-+        if (lines == null) { lines = new String[]{"", "", "", ""}; } // Paper
-     }
- 
-     public CraftSign(final Material material, final TileEntitySign te) {
-         super(material, te);
-+        if (lines == null) { lines = new String[]{"", "", "", ""}; } // Paper
-     }
- 
-     @Override
 diff --git a/src/main/java/org/bukkit/craftbukkit/persistence/CraftPersistentDataContainer.java b/src/main/java/org/bukkit/craftbukkit/persistence/CraftPersistentDataContainer.java
 index 58e2db5da178af6a8c30f563353fefe720ff9781..b704f550de290e0bc1235bf7e68c7eb347162c69 100644
 --- a/src/main/java/org/bukkit/craftbukkit/persistence/CraftPersistentDataContainer.java