### 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_COND_V(p_caret > carets.size(), "");
	StringBuilder selected_text;
	Vector<int> caret_edit_order = get_caret_index_edit_order();
	for (int i = caret_edit_order.size() - 1; i >= 0; i--) {
		int caret_idx = caret_edit_order[i];
		if (p_caret != -1 && p_caret != caret_idx) {
			continue;
		}
		if (!has_selection(caret_idx)) {
			continue;
		}
		selected_text += _base_get_text(get_selection_from_line(caret_idx), get_selection_from_column(caret_idx), get_selection_to_line(caret_idx), get_selection_to_column(caret_idx));
		if (p_caret == -1 && i != 0) {
			selected_text += "\n";
		}
	}
	return selected_text.as_string();
}
int TextEdit::get_selection_line(int p_caret) const {