### Godot version

4.0.2.stable.official [7a0977ce2]

### System information

Windows 10

### Issue description

LineEdit node with enabled "expand_to_text_length" option and "minimum_character_width = 0" and cleared margins in style overrides still has some empty space inside
![node](https://github.com/godotengine/godot/assets/23380802/86c79678-8422-4a98-8406-602edd7dc48b)
![node settings](https://github.com/godotengine/godot/assets/23380802/11d04d71-bbf1-4c16-8155-fe39b5bbd66b)
![style overrides](https://github.com/godotengine/godot/assets/23380802/6b3c3925-b4bd-455b-aac1-ddeb54a4d796)


### Steps to reproduce

1. Add LineEdit node
2. Set expand_to_text_length = true
3. Set minimum_character_width in theme overrides = 0
4. Set normal to StyleBoxEmpty


### Minimal reproduction project

[LineEdit can't be zero sized.zip](https://github.com/godotengine/godot/files/11566017/LineEdit.can.t.be.zero.sized.zip)

}
	Ref<InputEventMouseMotion> m = p_event;
	if (m.is_valid()) {
		if (!text.is_empty() && is_editable() && clear_button_enabled) {
			bool last_press_inside = clear_button_status.pressing_inside;
			clear_button_status.pressing_inside = clear_button_status.press_attempt && _is_over_clear_button(m->get_position());
			if (last_press_inside != clear_button_status.pressing_inside) {
				queue_redraw();
			}
		}
		if (m->get_button_mask().has_flag(MouseButtonMask::LEFT)) {
			if (selection.creating) {
				set_caret_at_pixel_pos(m->get_position().x);
				selection_fill_at_caret();
			}
		}
		if (drag_action && can_drop_data(m->get_position(), get_viewport()->gui_get_drag_data())) {
			drag_caret_force_displayed = true;
			set_caret_at_pixel_pos(m->get_position().x);
		}
		return;
	}
	Ref<InputEventKey> k = p_event;
	if (k.is_valid()) {
		if (!k->is_pressed()) {
			if (alt_start && k->get_keycode() == Key::ALT) {
				alt_start = false;
				if ((alt_code > 0x31 && alt_code < 0xd800) || (alt_code > 0xdfff && alt_code <= 0x10ffff)) {
					char32_t ucodestr[2] = { (char32_t)alt_code, 0 };
					insert_text_at_caret(ucodestr);