This snippet is used to prevent the emails that are sent when things are auto updated within WordPress

mu-stop-update-emails.php

<?php
/**
 * Disable Auto Update Emails
 * 
 * Plugin Name:     Disable Auto Update Emails
 * Description:     Disable the emails that are sent when plugins, themes, and WP Core are auto updated.
 * Version:         0.1.0
 * Author:          Paul Stoute
 * Author URI:      https://stoute.co
 * License:         GPL-2.0+
 * License URI:     http://www.gnu.org/licenses/gpl-2.0.txt
 */


// Stop the auto update emails for WP Core updates

add_filter( 'auto_core_update_send_email', 'wpb_stop_auto_update_emails', 10, 4 );
 
function stop_update_emails( $send, $type, $core_update, $result ) {
if ( ! empty( $type ) && $type == 'success' ) {
return false;
}
return true;
}

// Stop the auto update emails for plugins
add_filter( 'auto_plugin_update_send_email', '__return_false' );

// Stop the auto update emails for themes
add_filter( 'auto_theme_update_send_email', '__return_false' );