Remove use-server-properties-name option

This was removed from Minecraft 1.14, and isn't something I feel was ever really necessary to support.

bukkit/src/main/java/me/lucko/luckperms/bukkit/LPBukkitBootstrap.java

@@ -212,11 +212,6 @@ public class LPBukkitBootstrap extends JavaPlugin implements LuckPermsBootstrap
         return getServer().getVersion() + " - " + getServer().getBukkitVersion();
     }
 
-    @Override
-    public String getServerName() {
-        return getServer().getServerName();
-    }
-
     @Override
     public Path getDataDirectory() {
         return getDataFolder().toPath().toAbsolutePath();

bukkit/src/main/resources/config.yml

@@ -556,10 +556,6 @@ vault-debug: false
 # - Useful if you're having issues with UUID forwarding or data not being loaded.
 debug-logins: false
 
-# If LuckPerms should use the "server-name" property from the "server.properties" file as the
-# "server" option within LuckPerms.
-use-server-properties-name: false
-
 # If LuckPerms should allow usernames with non alphanumeric characters.
 #
 # - Note that due to the design of the storage implementation, usernames must still be 16 characters