Avoid NPE due to PlayerBedFailEnterEvent

fixes #5670

Spigot-Server-Patches/0715-Added-PlayerBedFailEnterEvent.patch

@@ -17,7 +17,7 @@ index 3a13e7a050db7f5c93d810afe56325495cec7aa4..c39c50e53549e9cb9d3520bc7e8b7e89
          public IChatBaseComponent a() {
              return this.g;
 diff --git a/src/main/java/net/minecraft/world/level/block/BlockBed.java b/src/main/java/net/minecraft/world/level/block/BlockBed.java
-index eca84595342756e3550883551e487aaf79574fde..abe0a1c309d526de37efcac44922fa259e1d112c 100644
+index eca84595342756e3550883551e487aaf79574fde..00a01a157deec004bcf2f8587723a0ecd0bfef85 100644
 --- a/src/main/java/net/minecraft/world/level/block/BlockBed.java
 +++ b/src/main/java/net/minecraft/world/level/block/BlockBed.java
 @@ -43,6 +43,8 @@ import net.minecraft.world.phys.shapes.VoxelShape;
@@ -29,7 +29,7 @@ index eca84595342756e3550883551e487aaf79574fde..abe0a1c309d526de37efcac44922fa25
  
  public class BlockBed extends BlockFacingHorizontal implements ITileEntity {
  
-@@ -101,14 +103,22 @@ public class BlockBed extends BlockFacingHorizontal implements ITileEntity {
+@@ -101,14 +103,23 @@ public class BlockBed extends BlockFacingHorizontal implements ITileEntity {
                  BlockPosition finalblockposition = blockposition;
                  // CraftBukkit end
                  entityhuman.sleep(blockposition).ifLeft((entityhuman_enumbedresult) -> {
@@ -48,7 +48,8 @@ index eca84595342756e3550883551e487aaf79574fde..abe0a1c309d526de37efcac44922fa25
                      // CraftBukkit end
                      if (entityhuman_enumbedresult != null) {
 -                        entityhuman.a(entityhuman_enumbedresult.a(), true);
-+                        entityhuman.a(PaperAdventure.asVanilla(event.getMessage()), true); // Paper
++                        final net.kyori.adventure.text.Component message = event.getMessage(); // Paper
++                        if(message != null) entityhuman.a(PaperAdventure.asVanilla(message), true); // Paper
                      }
 +                    } // Paper