### Godot version

v4.0.beta.custom_build [13f0158]

### System information

Windows 10

### Issue description

When doing operations (`begin_complex_operation` and `end_complex_operation`) with multiple selections in TextEdit, some of these selections don't revert upon undo. This behavior is affects some of script editor's operations, like duplicate selection and delete lines.

### Steps to reproduce

Open script editor, make multiple selections. Keep in mind what you have selected. Do duplicate selection (ctrl+shift+D). Undo (ctrl+Z). Compare the result to what you remember.

### Minimal reproduction project

N/A
if (!selecting_enabled) {
		return;
	}
	if (!has_selection(p_caret) || get_selection_mode() == SelectionMode::SELECTION_MODE_NONE) {
		carets.write[p_caret].selection.active = true;
		set_selection_mode(SelectionMode::SELECTION_MODE_SHIFT, get_caret_line(p_caret), get_caret_column(p_caret), p_caret);
		return;
	}
	set_selection_mode(SelectionMode::SELECTION_MODE_SHIFT, get_selection_line(p_caret), get_selection_column(p_caret), p_caret);
}
void TextEdit::_post_shift_selection(int p_caret) {