### Godot version

4.0

### System information

Windows 10 x64

### Issue description

We have an established way to inform about invalid input fields: using red/green/yellow labels at the bottom:
![](https://user-images.githubusercontent.com/2223172/235779087-7db4a899-dd41-40c7-8cb3-b295a42eec5e.png)
It's used in Create New Scene dialog, Add Metadata dialog, New Folder dialog, Create Script dialog and probably others.

Meantime the New Plugin dialog (accessible in Project Settings -> Plugins) looks like this:
![image](https://user-images.githubusercontent.com/2223172/235783588-ef5e560c-8620-4017-9b50-86f8477fe40e.png)
Instead of info labels, it uses info icons that show message on hover. This dialog was created before we had an established way of validating input, so it needs updating.

### Steps to reproduce

1. Project
2. Project Settings
3. Plugins
4. Create New Plugin
5. 👀

### Minimal reproduction project

N/A
#ifndef PLUGIN_CONFIG_DIALOG_H
#define PLUGIN_CONFIG_DIALOG_H
#include "scene/gui/check_box.h"
#include "scene/gui/dialogs.h"
#include "scene/gui/line_edit.h"
#include "scene/gui/option_button.h"
#include "scene/gui/text_edit.h"
#include "scene/gui/texture_rect.h"
class PluginConfigDialog : public ConfirmationDialog {