Cron API: Clear the recovery_mode_clean_expired_keys cron event when converting a single site installation to Multisite.

This cron event is not used when Multisite is in use.

Props debarghyabanerjee, johnbillion, narenin

Fixes #61450

git-svn-id: https://develop.svn.wordpress.org/trunk@59798 602fd350-edb4-49c9-b593-d223f7449a82

Author: johnbillion

src/wp-admin/includes/schema.php

@@ -1047,6 +1047,11 @@ function populate_network( $network_id = 1, $domain = '', $email = '', $site_nam
 		)
 	);
 
+	// Remove the cron event since Recovery Mode is not used in Multisite.
+	if ( wp_next_scheduled( 'recovery_mode_clean_expired_keys' ) ) {
+		wp_clear_scheduled_hook( 'recovery_mode_clean_expired_keys' );
+	}
+
 	/*
 	 * When upgrading from single to multisite, assume the current site will
 	 * become the main site of the network. When using populate_network()