[PERFOMANCE] Sync chunk load before processing chunk async..

[Kaan0104]

Timings Not required

Is the plugin up to date? Yes

Server Environment & Version Paper 1.21.1

Additional Information (Optional) We are performing the chunk getting async with the paperlib, however on line 56 we are getting the y coordinate through World#getHighestBlockYAt which will call the chunk sync if the chunk wasnt loaded before.