### 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)

_THREAD_SAFE_METHOD_
	if (!windows.has(last_focused_window)) {
		return String(); 
	}
	String ret;
	if (!OpenClipboard(windows[last_focused_window].hWnd)) {
		ERR_FAIL_V_MSG("", "Unable to open clipboard.");
	}
	if (IsClipboardFormatAvailable(CF_UNICODETEXT)) {
		HGLOBAL mem = GetClipboardData(CF_UNICODETEXT);
		if (mem != nullptr) {
			LPWSTR ptr = (LPWSTR)GlobalLock(mem);
			if (ptr != nullptr) {
				ret = String::utf16((const char16_t *)ptr);
				GlobalUnlock(mem);