SPIGOT-6508: Rename conflicted getServer

By: md_5 <git@md-5.net>

paper-server/nms-patches/net/minecraft/world/level/block/BlockConcretePowder.patch

@@ -62,7 +62,7 @@
 +            blockState.setData(this.concrete);
 +
 +            BlockFormEvent event = new BlockFormEvent(blockState.getBlock(), blockState);
-+            ((World) generatoraccess).getServer().getPluginManager().callEvent(event);
++            ((World) generatoraccess).getCraftServer().getPluginManager().callEvent(event);
 +
 +            if (!event.isCancelled()) {
 +                return blockState.getHandle();