### 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.
Ref<InputEventKey> k = p_event;
	if (k.is_valid()) {
		if (!k->is_pressed()) {
			return;
		}
		
		if (has_focus() && editable && (k->get_unicode() >= 32)) {
			selection_delete();
			char32_t ucodestr[2] = { (char32_t)k->get_unicode(), 0 };
			int prev_len = text.length();
			insert_text_at_caret(ucodestr);
			if (text.length() != prev_len) {
				_text_changed();
			}
			accept_event();
		}
	}
}
void LineEdit::gui_input(const Ref<InputEvent> &p_event) {