Docs: Add missing @global descriptions in wp-admin/includes/schema.php.

Follow-up to [32643], [45734].

Props noruzzaman, huzaifaalmesbah, shailu25, sabernhardt.
See #64224.

git-svn-id: https://develop.svn.wordpress.org/trunk@61592 602fd350-edb4-49c9-b593-d223f7449a82

Author: SergeyBiryukov

src/wp-admin/includes/schema.php

@@ -12,8 +12,8 @@
  * Declare these as global in case schema.php is included from a function.
  *
  * @global wpdb   $wpdb            WordPress database abstraction object.
- * @global array  $wp_queries
- * @global string $charset_collate
+ * @global array  $wp_queries      Global database queries array.
+ * @global string $charset_collate Database charset and collation.
  */
 global $wpdb, $wp_queries, $charset_collate;