Remove login on wordpress site

index.php

<?php
/*
Plugin Name: Remove login.
Description: Plugin that removes login WordPress, useful on testing environments. Should never be used on production.
Author: Marius Cristea
Version: 0.0.1
*/

add_action( 'after_setup_theme', function () {
	if ( ! is_user_logged_in() ) {
		$autologin_user = wp_signon(
			[
				'user_login'    => 'admin',
				'user_password' => 'admin',
				'remember'      => true
			],
			false
		);
		if ( ! is_wp_error( $autologin_user ) ) {
			header( 'Location: wp-admin' );
		}
	}
} );

add_filter( 'rest_authentication_errors', function () {
	wp_set_current_user( 1 ); 
}, 101 );