### Godot version

4.0 beta 15

### System information

Windows 10

### Issue description

It happened with both Google IME and MS-IME, and there was no problem until Beta14.
When typing Japanese characters, it is common to select a character from the suggestion window and then start typing the next character before confirming.
In this case, uncommitted characters are forcibly committed, and input of the next character begins.

**↓Beta15**

https://user-images.githubusercontent.com/186786/214753450-b493cca6-2644-4b3d-8cd2-660565cc3547.mp4

**↓Beta14**

https://user-images.githubusercontent.com/186786/214755127-dde819cc-4d63-403a-99b0-09821671f74e.mp4



### Steps to reproduce

It happened with both Google IME and MS-IME in beta15

### Minimal reproduction project

It is project independent and happens in the editor.
mm->set_shift_pressed((wParam & MK_SHIFT) != 0);
			mm->set_alt_pressed(alt_mem);
			if ((tablet_get_current_driver() == "wintab") && wintab_available && windows[window_id].wtctx) {
				
				if (windows[window_id].last_pressure_update < 10) {
					windows[window_id].last_pressure_update++;
				} else {
					windows[window_id].last_tilt = Vector2();
					windows[window_id].last_pressure = (wParam & MK_LBUTTON) ? 1.0f : 0.0f;
					windows[window_id].last_pen_inverted = false;
				}
			} else {
				windows[window_id].last_tilt = Vector2();
				windows[window_id].last_pressure = (wParam & MK_LBUTTON) ? 1.0f : 0.0f;
				windows[window_id].last_pen_inverted = false;
			}
			mm->set_pressure(windows[window_id].last_pressure);
			mm->set_tilt(windows[window_id].last_tilt);
			mm->set_pen_inverted(windows[window_id].last_pen_inverted);
			mm->set_button_mask(last_button_state);
			mm->set_position(Vector2(GET_X_LPARAM(lParam), GET_Y_LPARAM(lParam)));
			mm->set_global_position(Vector2(GET_X_LPARAM(lParam), GET_Y_LPARAM(lParam)));
			if (mouse_mode == MOUSE_MODE_CAPTURED) {
				Point2i c(windows[window_id].width / 2, windows[window_id].height / 2);
				old_x = c.x;
				old_y = c.y;
				if (mm->get_position() == c) {
					center = c;
					return 0;
				}