'Editable Children' or 'Load as Placeholder' don't mark the scene as dirty (asterisk)

[Flavelius]

Godot version

3.5 rc5 mono

System information

Windows 10

Issue description

When toggling 'Load as Placeholder' or 'Editable Children' the containing scene is not marked with an asterisk that indicates that something has changed and needs to be saved, not sure if that also applies to internal dirty checks, but atleast visually it's missing.

Steps to reproduce

Open a scene, instantiate a packedscene in it, make sure the outer scene is not in a 'changed' state (no asterisk in title-tab) by saving it once somewhere, then change one of the mentioned toggles on the instanced scene in it and notice the asterisk/dirty indicator not appearing even though toggling those options should produce a change in the resulting file.

Minimal reproduction project

No response

[KoBeWi]

This is because toggling them isn't stored in the undo history.

[AThousandShips]

True for 4.0 as well

[AThousandShips]

Related PR: #46057