Guidelines for hiDPI support in Multiple Resolutions tutorial are outdated and incomplete

[lostminds]

Your Godot version:
Godot 4.2.dev6

Issue description:
The guidelines for hiDPI support in Multiple Resolutions tutorial are outdated and incomplete. They state that the setting is not enabled by default (which it is now), but indicate you can just turn it on to get hiDPI support. However, enabling the setting (now default) just makes everything smaller on hiDPI monitors, so perhaps it would be helpful to add that to actually get the higher resolution rendering you also need to increase the window content_scale_factor and size (as described in this related proposal godotengine/godot-proposals#7968)

URL to the documentation page:
https://docs.godotengine.org/en/stable/tutorials/rendering/multiple_resolutions.html#hidpi-support

[HoofedEar]

Adding to this, the article still makes reference to setting min_window_size() via OS when in Godot 4, these functions got moved to DisplayServer

[skyace65]

Fixed by #9037. There's another PR already open for HoofedEar's issue. Also please do not report a different issue in the comments of an existing issue.