Do not schedule poi task for each block write on chunk gen

Most of the time optional == optional1, so we shouldn't
schedule a task for each write.

Spigot-Server-Patches/Remove-stale-POIs.patch

@@ -9,23 +9,17 @@ index 0000000000000000000000000000000000000000..00000000000000000000000000000000
 --- a/src/main/java/net/minecraft/server/level/WorldServer.java
 +++ b/src/main/java/net/minecraft/server/level/WorldServer.java
 @@ -0,0 +0,0 @@ public class WorldServer extends World implements GeneratorAccessSeed {
-         Optional<VillagePlaceType> optional = VillagePlaceType.b(iblockdata);
-         Optional<VillagePlaceType> optional1 = VillagePlaceType.b(iblockdata1);
- 
-+        // Paper start
-+        BlockPosition blockposition1 = blockposition.immutableCopy();
-+        this.getMinecraftServer().execute(() -> {
-+                if (!optional.isPresent() && this.getPoiStorage().test(blockposition1, com.google.common.base.Predicates.alwaysTrue())) {
-+                    this.getPoiStorage().remove(blockposition1);
-+                }
-+        });
-         if (!Objects.equals(optional, optional1)) {
--            BlockPosition blockposition1 = blockposition.immutableCopy();
-+            //BlockPosition blockposition1 = blockposition.immutableCopy();
-+            // Paper end
- 
-             optional.ifPresent((villageplacetype) -> {
+             });
+             optional1.ifPresent((villageplacetype) -> {
                  this.getMinecraftServer().execute(() -> {
++                    // Paper start
++                    if (!optional.isPresent() && this.getPoiStorage().test(blockposition1, com.google.common.base.Predicates.alwaysTrue())) {
++                        this.getPoiStorage().remove(blockposition1);
++                    }
++                    // Paper end
+                     this.y().a(blockposition1, villageplacetype);
+                     PacketDebug.a(this, blockposition1);
+                 });
 @@ -0,0 +0,0 @@ public class WorldServer extends World implements GeneratorAccessSeed {
          }
      }