Docs: Second pass at replacing Codex URLs with a corresponding HelpHub or DevHub article.

Follow-up to [45674-45677].

Props marcio-zebedeu, zodiac1978, netweb.
See #48987.
Built from https://develop.svn.wordpress.org/trunk@49912


git-svn-id: http://core.svn.wordpress.org/trunk@49611 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/wp-db.php

@@ -1887,11 +1887,11 @@ class wpdb {
 	/**
 	 * Performs a MySQL database query, using current database connection.
 	 *
-	 * More information can be found on the Codex page.
+	 * More information can be found on the documentation page.
 	 *
 	 * @since 0.71
 	 *
-	 * @link https://codex.wordpress.org/Function_Reference/wpdb_Class
+	 * @link https://developer.wordpress.org/reference/classes/wpdb/
 	 *
 	 * @param string $query Database query.
 	 * @return int|bool Boolean true for CREATE, ALTER, TRUNCATE and DROP queries. Number of rows