### 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
author_edit->set_h_size_flags(Control::SIZE_EXPAND_FILL);
	grid->add_child(author_edit);
	
	Label *version_lb = memnew(Label);
	version_lb->set_text(TTR("Version:"));
	version_lb->set_horizontal_alignment(HORIZONTAL_ALIGNMENT_RIGHT);
	grid->add_child(version_lb);
	Control *version_spacer = memnew(Control);
	grid->add_child(version_spacer);
	version_edit = memnew(LineEdit);
	version_edit->set_placeholder("1.0");
	version_edit->set_h_size_flags(Control::SIZE_EXPAND_FILL);
	grid->add_child(version_edit);
	
	Label *script_option_lb = memnew(Label);
	script_option_lb->set_text(TTR("Language:"));
	script_option_lb->set_horizontal_alignment(HORIZONTAL_ALIGNMENT_RIGHT);
	grid->add_child(script_option_lb);
	Control *script_opt_spacer = memnew(Control);
	grid->add_child(script_opt_spacer);
	script_option_edit = memnew(OptionButton);
	int default_lang = 0;
	for (int i = 0; i < ScriptServer::get_language_count(); i++) {
		ScriptLanguage *lang = ScriptServer::get_language(i);
		script_option_edit->add_item(lang->get_name());
		if (lang->get_name() == "GDScript") {
			default_lang = i;
		}
	}
	script_option_edit->select(default_lang);