r43008 refactored the request flow to make several improvements, but accidentally marked `completed` requests as `confirmed`. This commit restores the intended statuses, so that the data and corresponding UI reflect reality.
Props allendav, birgire.
Merges [43183] to the 4.9 branch.
Fixes#43913.
Built from https://develop.svn.wordpress.org/branches/4.9@43187
git-svn-id: http://core.svn.wordpress.org/branches/4.9@43016 1a063a9b-81f0-0310-95a4-ce76da25c4cd