Fix docs and white space.

Props desrosj.
See #43443.

git-svn-id: https://develop.svn.wordpress.org/trunk@43014 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-includes/user.php

@@ -2950,6 +2950,8 @@ function wp_user_request_action_description( $action_name ) {
 	/**
 	 * Filters the user action description.
 	 *
+	 * @since 4.9.6
+	 *
 	 * @param string $description The default description.
 	 * @param string $action_name The name of the request.
 	 */