[FIX] project: default project on task

Before this commit, Project on new Tasks created from Project's Kanban was always empty as we are not setting `default_project_id` in the context.

Now we add `default_project_id` in the context to set the default Project on tasks.

Fixes #49446

closes odoo/odoo#49448

Signed-off-by: Yannick Tivisse (yti) <yti@odoo.com>