Site Health: Use a front-end URL for loopback tests.

In [49154] the async Site Health tests were changed to use the REST API instead of admin-ajax. An unintended side effect of this change was that the loopback tests which tried to ping the site's `admin_url()` were no longer authenticated because admin-cookies aren't provided to the REST API.

This commit adjusts the loopback test to use the front-end `site_url` which checks that cron will function properly. A follow-up ticket will focus on tests that will cover the file editor checks.

Props Clorith.
Fixes #52097.
See #48105.

Built from https://develop.svn.wordpress.org/trunk@49917


git-svn-id: http://core.svn.wordpress.org/trunk@49616 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-admin/includes/class-wp-site-health.php

@@ -2545,7 +2545,7 @@ class WP_Site_Health {
 			$headers['Authorization'] = 'Basic ' . base64_encode( wp_unslash( $_SERVER['PHP_AUTH_USER'] ) . ':' . wp_unslash( $_SERVER['PHP_AUTH_PW'] ) );
 		}
 
-		$url = admin_url();
+		$url = site_url();
 
 		$r = wp_remote_get( $url, compact( 'cookies', 'headers', 'timeout', 'sslverify' ) );
 

wp-includes/version.php

@@ -13,7 +13,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '5.7-alpha-49916';
+$wp_version = '5.7-alpha-49917';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.