### 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.
ERR_FAIL_INDEX(p_from_line, text.size());
	ERR_FAIL_INDEX(p_from_column, text[p_from_line].length() + 1);
	ERR_FAIL_INDEX(p_to_line, text.size());
	ERR_FAIL_INDEX(p_to_column, text[p_to_line].length() + 1);
	ERR_FAIL_COND(p_to_line < p_from_line); 
	ERR_FAIL_COND(p_to_line == p_from_line && p_to_column < p_from_column); 
	String pre_text = text[p_from_line].substr(0, p_from_column);
	String post_text = text[p_to_line].substr(p_to_column, text[p_to_line].length());
	text.remove_range(p_from_line, p_to_line);
	text.set(p_from_line, pre_text + post_text, structured_text_parser(st_parser, st_args, pre_text + post_text));
	if (!text_changed_dirty && !setting_text) {
		if (is_inside_tree()) {
			MessageQueue::get_singleton()->push_call(this, "_text_changed_emit");
		}
		text_changed_dirty = true;
	}
	emit_signal(SNAME("lines_edited_from"), p_to_line, p_from_line);
}
TextEdit::TextEdit(const String &p_placeholder) {
	placeholder_data_buf.instantiate();
	carets.push_back(Caret());
	clear();
	set_focus_mode(FOCUS_ALL);
	_update_caches();
	set_default_cursor_shape(CURSOR_IBEAM);