Display warning when selecting Group template outside of the group

What does this MR do and why?

Contributes to #208500 (closed)

Problem

When user selects a Group template outside of the group page, then we don't know where should we create the new project. By default, we select the template location which is not expected.

Solution

Don't allow to create new projects with Group template if group is not provided.

Screenshots or screen recordings

No group templates	Group template exist, from the group	Group template exist, outside of group ( New )

How to set up and validate locally

Numbered steps to set up and validate the change are strongly suggested.

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