Bug 17920: t/db_dependent/Sitemapper.t fails because of permissions

Bug 17920: t/db_dependent/Sitemapper.t fails because of permissions

The directory it attempts to create an xml file may not be writable for
the user running the test. By changing the directory from the current
directory to a temporary one, the test runs. After all 'chmod 777
t/db_dependent' is a bad idea.

TEST PLAN
---------
1) sudo koha-shell "prove t/db_dependent/Sitemapper.t" kohadev
   -- fails
2) apply patch
3) sudo koha-shell "prove t/db_dependent/Sitemapper.t" kohadev
   -- succeeds
4) run koha qa test tools

Tested without qa tools
Signed-off-by: Claire Gravely <claire_gravely@hotmail.com>
Signed-off-by: Marcel de Rooy <m.de.rooy@rijksmuseum.nl>
Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>