Add spigot api-version back to fix warning in console (#6)

* Avoid using System.out.print/err

* Remove register protocol debug message entirely

* remove #protocolService in Protocol

* Add api-version to fix warnings in the console

---------

Co-authored-by: Nico Middendorf <[email protected]>

Author: RappyTV

server/bukkit/src/main/resources/plugin.yml

@@ -1,3 +1,4 @@
 name: LabyModServerAPI
 version: '${version}'
+api-version: '1.13'
 main: net.labymod.serverapi.server.bukkit.LabyModServerAPIPlugin