2D stretch mode doesn't scale properly

[abueide]

Godot version:

4.0, b55d859

OS/device including version:

Windows, Vulkan

Issue description:

I set my resolution to 320x180. I set the test resolution to scale up to 1280x720. I set the stretch mode to 2D. When I start the game the camera is really far zoomed out, and doesn't show the camera region that is represented in the editor. When I resize the window, it doesn't stretch the content, it just stays the same size and shows more of the screen.

Steps to reproduce:
Open repro project, run game.

Minimal reproduction project:

repro.zip

[Calinou]

Related to #37941.

[txj-mssl]

I have this problem, too

[akien-mga]

Duplicate of #37941.