default FunctionalCommandBuilder<ConsoleCommandSender> assertConsole() {
        return assertConsole(DEFAULT_NOT_CONSOLE_MESSAGE);
    }
Asserts that the sender is instance of ConsoleCommandSender, and sends them the default failure message if
they're not.

@return the builder instance
helper/src/main/java/me/lucko/helper/command/functional/FunctionalCommandBuilder.java