Replaces a static string

src/main/java/net/knarcraft/bookswithoutborders/command/CommandGive.java

@@ -32,7 +32,7 @@ public class CommandGive implements TabExecutor {
     public boolean onCommand(@NotNull CommandSender sender, @NotNull Command command, @NotNull String label,
                              @NotNull String[] arguments) {
         if (!(sender instanceof Player)) {
-            BooksWithoutBorders.sendErrorMessage(sender, "This command can only be used by a player!");
+            BooksWithoutBorders.getStringFormatter().displayErrorMessage(sender, Translatable.ERROR_PLAYER_ONLY);
             return false;
         }