testXHTML: fix business template installation order

This test (just like all legacy filesystem tests) does not use business
template dependencies but just install business templates in the order from
getBusinessTemplateList, but business templates are not listed in correct
order.

It use to be OK (which warnings), but erp5_test_result can no longer be
installed without erp5_project, so review installation order to install
erp5_project earlier.