WordPress at a glance
action is not described

woocommerce_update_options action-hook . WC 1.0

Trigger actions.

Usage

add_action( 'woocommerce_update_options', 'action_function_name_3116' );
function action_function_name_3116(){
	// action...
}

Where the hook is called

WC_Admin_Settings::save()
woocommerce_update_options
woocommerce/includes/admin/class-wc-admin-settings.php 79
do_action( 'woocommerce_update_options' );

Where in WP core the hook is used WooCommerce

woocommerce/includes/tracks/events/class-wc-settings-tracking.php 35
add_action( 'woocommerce_update_options', array( $this, 'send_settings_change_event' ) );