Coding Standards: Use strict comparison for $wp_db_version check in…

… `wp-admin/network/upgrade.php`.

Follow-up to [47787], [47788].

See #50155, #49542.

git-svn-id: https://develop.svn.wordpress.org/trunk@47852 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-admin/network/upgrade.php

@@ -90,6 +90,7 @@
 					'sslverify'   => false,
 				)
 			);
+
 			if ( is_wp_error( $response ) ) {
 				wp_die(
 					sprintf(
@@ -109,6 +110,7 @@
 			 * @param array|WP_Error $response The upgrade response array or WP_Error on failure.
 			 */
 			do_action( 'after_mu_upgrade', $response );
+
 			/**
 			 * Fires after each site has been upgraded.
 			 *
@@ -132,7 +134,7 @@ function nextpage() {
 		break;
 	case 'show':
 	default:
-		if ( get_site_option( 'wpmu_upgrade_site' ) != $GLOBALS['wp_db_version'] ) :
+		if ( (int) get_site_option( 'wpmu_upgrade_site' ) !== $GLOBALS['wp_db_version'] ) :
 			?>
 		<h2><?php _e( 'Database Update Required' ); ?></h2>
 		<p><?php _e( 'WordPress has been updated! Before we send you on your way, we need to individually upgrade the sites in your network.' ); ?></p>