Bug 10640: (follow-up) bump up the number of expected tests in Bookseller.t

Signed-off-by: Galen Charlton <gmc@esilibrary.com>

t/db_dependent/Bookseller.t

@@ -2,7 +2,7 @@
 
 use Modern::Perl;
 
-use Test::More tests => 54;
+use Test::More tests => 55;
 use C4::Context;
 use Koha::DateUtils;
 use DateTime::Duration;