Move page: allow parent without any pages sections

[distantnative]

Description

• Unit test

Summary of changes

• Allow any templates as children for a page that does not define any pages sections or only sections with no template restrictions

Reasoning

It's confusing why currently no template is accepted when moving, while no template restrictions exists for the page.

Additional context

Could be seen a breaking change but I think the current behavior is more a unexpected bug.

Changelog

Fixes

• Page move rules: allow any template if no pages section in parent #6716

Ready?

• In-code documentation (wherever needed)
• Unit tests for fixed bug/feature
• Tests and CI checks all pass

For review team

• Add changes & docs to release notes draft in Notion

[bastianallgeier]

I remember that I thought that a page should only really be allowed to have children if this is defined with page sections. But I think I agree now after a while that this is too strict. If you move a page into another page that does not have any page sections, nothing bad will truly happen. The only problem might be that you are no longer able to find that page later, except by searching it.