Networks and Sites: Set `WP_Network` properties via setters upon creation.

This ensures that `WP_Network::$id` is stored internally as `int`, to match the documented type.

Follow-up to [37870].

Props ironprogrammer, scottculverhouse, spacedmonkey, SergeyBiryukov.
See #62035.
Built from https://develop.svn.wordpress.org/trunk@59020


git-svn-id: http://core.svn.wordpress.org/trunk@58416 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/class-wp-network.php

@@ -131,7 +131,7 @@ class WP_Network {
 	 */
 	public function __construct( $network ) {
 		foreach ( get_object_vars( $network ) as $key => $value ) {
-			$this->$key = $value;
+			$this->__set( $key, $value );
 		}
 
 		$this->_set_site_name();

wp-includes/version.php

@@ -16,7 +16,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '6.7-alpha-59019';
+$wp_version = '6.7-alpha-59020';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.