Since 12bc2ab, there are two projects created for each SO
instead of one in the demo data.
This is because in the sale lines, one product creates a project
with a template, but others create a project without a template,
which creates two projects.
This commit adds a project template to the products without one to
create a single project per SO.
closes odoo/odoo#94514
Signed-off-by: Laurent Stukkens (ltu) <ltu@odoo.com>