Disable delayed chunk unloads by default

While the option remains a powerful tool we recommend everyone use, 30s is
proving to be a bit much for certain gametypes and many admins are confused
that after updating they are now facing extreme loaded chunk counts.

We do recommend experienced users configure this value as needed, but we
cannot keep it as a default option given the variety of gametypes, the
potential inexperience of new users, and previous users upgrading and
now facing extreme chunk counts that offer little benefit.

Spigot-Server-Patches/Delay-Chunk-Unloads-based-on-Player-Movement.patch

@@ -26,7 +26,7 @@ index 0000000000000000000000000000000000000000..00000000000000000000000000000000
  
 +    public long delayChunkUnloadsBy;
 +    private void delayChunkUnloadsBy() {
-+        delayChunkUnloadsBy = PaperConfig.getSeconds(getString("delay-chunk-unloads-by", "30s"));
++        delayChunkUnloadsBy = PaperConfig.getSeconds(getString("delay-chunk-unloads-by", "0s"));
 +        if (delayChunkUnloadsBy > 0) {
 +            log("Delaying chunk unloads by " + delayChunkUnloadsBy + " seconds");
 +            delayChunkUnloadsBy *= 1000;