### 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)

if (k->is_action("ui_text_caret_down", true) || k->is_action("ui_text_caret_line_end", true) || k->is_action("ui_text_caret_page_down", true)) {
			_move_caret_end(shift_pressed);
			accept_event();
			return;
		}
		
		if (k->is_action("ui_swap_input_direction", true)) {
			_swap_current_input_direction();
			accept_event();
			return;
		}
		_reset_caret_blink_timer();
		
		
		bool allow_unicode_handling = !(k->is_command_or_control_pressed() || k->is_ctrl_pressed() || k->is_alt_pressed() || k->is_meta_pressed());
		if (allow_unicode_handling && 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();
			return;
		}
	}
}
void LineEdit::set_horizontal_alignment(HorizontalAlignment p_alignment) {