Set the proper value for `wp_title()` when `is_author()` and `is_post_type_archive()` are both true. `post_type` should always win due to the precedence indicated in `get_queried_object()`.

Props mordauk.
Fixes #25398.



git-svn-id: https://develop.svn.wordpress.org/trunk@28251 602fd350-edb4-49c9-b593-d223f7449a82