### 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.
ts_caret.t_caret.position.y = TS->shaped_text_get_descent(rid);
													ts_caret.t_caret.size.y = caret_width;
												} else {
													ts_caret.t_caret.position.y = -TS->shaped_text_get_ascent(rid);
													ts_caret.t_caret.size.y = h;
												}
												ts_caret.t_caret.position += Vector2(char_margin + ofs_x, ofs_y);
												draw_rect(ts_caret.t_caret, caret_color, overtype_mode);
												if (ts_caret.l_caret != Rect2() && ts_caret.l_dir != ts_caret.t_dir) {
													
													ts_caret.l_caret.position += Vector2(char_margin + ofs_x, ofs_y);
													ts_caret.l_caret.size.x = caret_width;
													draw_rect(ts_caret.l_caret, caret_color);
													
													float d = (ts_caret.l_dir == TextServer::DIRECTION_LTR) ? 0.5 : -3;
													Rect2 trect = Rect2(ts_caret.l_caret.position.x + d * caret_width, ts_caret.l_caret.position.y + ts_caret.l_caret.size.y - caret_width, 3 * caret_width, caret_width);
													RenderingServer::get_singleton()->canvas_item_add_rect(ci, trect, caret_color);
												}
											} else { 
												if (gl_size > 0) {
													
													if (overtype_mode) {
														ts_caret.l_caret.position.y = TS->shaped_text_get_descent(rid);
														ts_caret.l_caret.size.y = caret_width;
													} else {
														ts_caret.l_caret.position.y = -TS->shaped_text_get_ascent(rid);
														ts_caret.l_caret.size.y = h;
													}
												} else if (overtype_mode) {
													ts_caret.l_caret.position.y += ts_caret.l_caret.size.y;