src/Setting/SettingStore.php
public function forget($key)
    {
        $this->unsaved = TRUE;

        if ($this->has($key)) {
            Arr::forget($this->items, $key);
        }
    }
public function forget($key)
    {
        $this->unsaved = TRUE;

        if ($this->has($key)) {
            Arr::forget($this->items, $key);
        }
    }
Unset a key in the settings data.

@param  string $key