### 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)

k = k->duplicate();
		bool shift_pressed = k->is_shift_pressed();
		
		k->set_shift_pressed(false);
		if (k->is_action("ui_text_caret_word_left", true)) {
			_move_caret_left(shift_pressed, true);
			accept_event();
			return;
		}
		if (k->is_action("ui_text_caret_left", true)) {
			_move_caret_left(shift_pressed);
			accept_event();
			return;
		}
		if (k->is_action("ui_text_caret_word_right", true)) {
			_move_caret_right(shift_pressed, true);
			accept_event();
			return;
		}
		if (k->is_action("ui_text_caret_right", true)) {
			_move_caret_right(shift_pressed, false);
			accept_event();
			return;
		}
		
		if (k->is_action("ui_text_caret_up", true) || k->is_action("ui_text_caret_line_start", true) || k->is_action("ui_text_caret_page_up", true)) {
			_move_caret_start(shift_pressed);
			accept_event();
			return;
		}