### Godot version

v4.0.beta15.official [4fa6edc88]

### System information

Windows 10

### Issue description

I use a custom keyboard layout (I made it myself), and it has «dead keys» (just like International keyboard layouts have). For example, if I press `'`, nothing happens, but if I press `a` after that, I'll get `á`. If I press `'` and `Space`, I'll get just `'`. And with my layout:
If I press `Shift + .` and then `a`, I will get `ᵄ`.
If I press `Shift + .` and then `Space`, I will get `>`.
If I press `Shift + [` and then `5`, I will get `₅`.
If I press `Shift + [` and then `Space`, I will get `{`.
In beta 14 and before, everything worked fine, but in beta 15 when I press `Shift + .` and `Space`, just nothing happens, I don't get `>`. Same for `Shift + [` and `Space`, I don't get `>`. It seems the problem is with `Shift`, because I still can type `á` (`'` and `a`) or `'` (`'` and `Space`), but not `ä` (`Shift + '` and `a`) or `"` (`Shift + '` and `Space`). In the latter cases I get `á` and `'` as if `Shift` were never pressed.

### Steps to reproduce

Install/add US International keyboard layout or [Extended Latin keyboard layout](https://github.com/godotengine/godot/files/10494466/Layouts.zip) (just run `Extended Latin\ExtLat6\setup.exe`).
Open script editor.
Press `Shift + '`.
Then press `a`.

### Minimal reproduction project

N/A
mm->set_velocity(Vector2(0, 0));
				if (raw->data.mouse.usFlags == MOUSE_MOVE_RELATIVE) {
					mm->set_relative(Vector2(raw->data.mouse.lLastX, raw->data.mouse.lLastY));
				} else if (raw->data.mouse.usFlags == MOUSE_MOVE_ABSOLUTE) {
					int nScreenWidth = GetSystemMetrics(SM_CXVIRTUALSCREEN);
					int nScreenHeight = GetSystemMetrics(SM_CYVIRTUALSCREEN);
					int nScreenLeft = GetSystemMetrics(SM_XVIRTUALSCREEN);
					int nScreenTop = GetSystemMetrics(SM_YVIRTUALSCREEN);
					Vector2 abs_pos(
							(double(raw->data.mouse.lLastX) - 65536.0 / (nScreenWidth)) * nScreenWidth / 65536.0 + nScreenLeft,
							(double(raw->data.mouse.lLastY) - 65536.0 / (nScreenHeight)) * nScreenHeight / 65536.0 + nScreenTop);
					POINT coords; 
					coords.x = abs_pos.x;
					coords.y = abs_pos.y;
					ScreenToClient(hWnd, &coords);
					mm->set_relative(Vector2(coords.x - old_x, coords.y - old_y));
					old_x = coords.x;
					old_y = coords.y;
				}
				if ((windows[window_id].window_has_focus || windows[window_id].is_popup) && mm->get_relative() != Vector2()) {
					Input::get_singleton()->parse_input_event(mm);
				}
			}
			delete[] lpb;
		} break;
		case WT_CSRCHANGE:
		case WT_PROXIMITY: {
			if ((tablet_get_current_driver() == "wintab") && wintab_available && windows[window_id].wtctx) {
				AXIS pressure;
				if (wintab_WTInfo(WTI_DEVICES + windows[window_id].wtlc.lcDevice, DVC_NPRESSURE, &pressure)) {