Fix Folia scheduler tasks not canceling when plugin disable

[LemonCaramel]

TestPlugin.java

public final class TestPlugin extends JavaPlugin implements Listener {

    @Override
    public void onEnable() {
        this.getServer().getPluginManager().registerEvents(this, this);

        this.getServer().getAsyncScheduler().runAtFixedRate(this, task -> {
            this.getLogger().info("Hello");
        }, 0L, 1L, TimeUnit.SECONDS);

        this.getServer().getScheduler().runTask(this, () -> {
            this.getServer().getPluginManager().disablePlugin(this);
        });
    }
}