### Godot version

4.0

### System information

Windows 11

### Issue description

So on my monitor with 2560x1440 resolution retrieved by the `DisplayServer.get_window_size` method shows 2562x1442, which I think is incorrect. A similar result returned by `get_viewport().size`. But it's become correct if the `Resizable` property is turned on.

![image](https://user-images.githubusercontent.com/3036176/212492776-5c09b12e-d25a-4951-8392-54f5a5e3bece.png)


### Steps to reproduce

Create the project, add a label to observe the resolution text, set the full-screen mode in the project settings, toggle off the `Resizable` property, and run the project.

### Minimal reproduction project

[TestResolution.zip](https://github.com/godotengine/godot/files/10418682/TestResolution.zip)

wd.wtlc.lcOutExtX = wd.wtlc.lcInExtX;
			wd.wtlc.lcOutOrgY = 0;
			wd.wtlc.lcOutExtY = -wd.wtlc.lcInExtY;
			wd.wtctx = wintab_WTOpen(wd.hWnd, &wd.wtlc, false);
			if (wd.wtctx) {
				wintab_WTEnable(wd.wtctx, true);
				AXIS pressure;
				if (wintab_WTInfo(WTI_DEVICES + wd.wtlc.lcDevice, DVC_NPRESSURE, &pressure)) {
					wd.min_pressure = int(pressure.axMin);
					wd.max_pressure = int(pressure.axMax);
				}
				AXIS orientation[3];
				if (wintab_WTInfo(WTI_DEVICES + wd.wtlc.lcDevice, DVC_ORIENTATION, &orientation)) {
					wd.tilt_supported = orientation[0].axResolution && orientation[1].axResolution;
				}
			} else {
				print_verbose("WinTab context creation failed.");
			}
		} else {
			wd.wtctx = 0;
		}
		if (p_mode == WINDOW_MODE_MAXIMIZED) {
			wd.maximized = true;
			wd.minimized = false;
		}
		if (p_mode == WINDOW_MODE_MINIMIZED) {
			wd.maximized = false;
			wd.minimized = true;
		}
		wd.last_pressure = 0;