PHP Notice: Undefined index: clear_trasients

The notice is triggered when saving EDD settings from a tab other than the Quaderno tab.

Here is the PHP stack:

PHP Notice: Undefined index: clear_trasients in ***/wp-content/plugins/edd-quaderno/includes/settings.php on line 83
PHP Stack trace:
PHP 1. {main}() ***/wp-admin/options.php:0
PHP 2. update_option() ***/wp-admin/options.php:322
PHP 3. do_action() ***/wp-includes/option.php:581
PHP 4. WP_Hook->do_action() ***/wp-includes/plugin.php:517
PHP 5. WP_Hook->apply_filters() ***/wp-includes/class-wp-hook.php:332
PHP 6. EDD_Email_Summary_Cron->settings_changed() ***/wp-includes/class-wp-hook.php:308
PHP 7. EDD_Email_Summary_Cron->schedule_cron_events() ***/wp-content/plugins/easy-digital-downloads/includes/emails/email-summary/class-edd-email-summary-cron.php:141
PHP 8. wp_schedule_single_event() ***/wp-content/plugins/easy-digital-downloads/includes/emails/email-summary/class-edd-email-summary-cron.php:88
PHP 9. _set_cron_array() ***/wp-includes/cron.php:197
PHP 10. update_option() ***/wp-includes/cron.php:1214
PHP 11. do_action() ***/wp-includes/option.php:581
PHP 12. WP_Hook->do_action() ***/wp-includes/plugin.php:517
PHP 13. WP_Hook->apply_filters() ***/wp-includes/class-wp-hook.php:332
PHP 14. clear_transients() ***/wp-includes/class-wp-hook.php:308

Best Regards,

José Andrés