Added support for new Spigot 1.20.2 build that uses mojang mappings for fields and methods (forks will probably follow as well).

Note on BungeeCord: There are still no news on 1.20.2 client support on BungeeCord. While the issue linked in previous update got closed, it got falsely closed - nothing was fixed. Shall a fix be introduced and plugin require an update to take advatange of the fix, plugin will be updated.