Coding Standards: Replace loose comparison in `wp-includes/ms-functio…

…ns.php`.

This brings more consistency with similar checks elsewhere.

Follow-up to [https://mu.trac.wordpress.org/changeset/1069 mu:1069], [12603].

Props debarghyabanerjee, audrasjb, jrf, aristath, SergeyBiryukov.
Fixes #62032.

git-svn-id: https://develop.svn.wordpress.org/trunk@59284 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-includes/ms-functions.php

@@ -1433,7 +1433,7 @@ function newblog_notify_siteadmin( $blog_id, $deprecated = '' ) {
 
 	$email = get_site_option( 'admin_email' );
 
-	if ( is_email( $email ) == false ) {
+	if ( ! is_email( $email ) ) {
 		return false;
 	}
 
@@ -1494,7 +1494,7 @@ function newuser_notify_siteadmin( $user_id ) {
 
 	$email = get_site_option( 'admin_email' );
 
-	if ( is_email( $email ) == false ) {
+	if ( ! is_email( $email ) ) {
 		return false;
 	}