Update sources of projects templates
Problem to solve
As highlighted in: https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/25776, projects can be created from the templates of two places.
Currently, the documentation for creating a project lists just one: https://docs.gitlab.com/ee/gitlab-basics/create-project.html#project-templates.
Proposal
Update references in https://docs.gitlab.com/ee/gitlab-basics/create-project.html from ... project-templates group to ... project-templates and pages groups