Fix off-by-one in async lighting neighbor loop

Spigot-Server-Patches/0042-Configurable-async-light-updates.patch

@@ -157,8 +157,8 @@ index b681a9f..8ee0cec 100644
 +        chunk.lightUpdateTime = chunk.world.getTime();
 +
 +        final List<Chunk> neighbors = new ArrayList<Chunk>();
-+        for (int cx = (x >> 4) - 1; cx < (x >> 4) + 1; ++cx) {
-+            for (int cz = (z >> 4) - 1; cz < (z >> 4) + 1; ++cz) {
++        for (int cx = (x >> 4) - 1; cx <= (x >> 4) + 1; ++cx) {
++            for (int cz = (z >> 4) - 1; cz <= (z >> 4) + 1; ++cz) {
 +                if (this.chunkProvider.isChunkLoaded(cx, cz)) {
 +                    Chunk neighbor = this.getChunkAt(cx, cz);
 +                    if (neighbor != chunk) {