### Godot version

4.0.beta13

### System information

Mageia 9, Linux

### Issue description

When exporting a trivial .NET project with 4.0.beta13, I get the following error:

```
ERROR: Required virtual method EditorExportPlugin::_get_name must be overridden before calling.
   at: _gdvirtual__get_name_call (editor/export/editor_export_plugin.h:123)
```

It doesn't seem to prevent exporting, but should be fixed anyway.

On the first export attempt (not be reproducible in my MRP, needs to be redone from scratch), it also shows this warning:
```
WARNING: Property not found: dotnet/project/assembly_name
     at: get_setting_with_override (core/config/project_settings.cpp:364)
```
Which likely means that we're using `GLOBAL_GET` before we defined the property with `GLOBAL_DEF`.

### Steps to reproduce

- Create a simple project with a hello world C# script
- Export it from Linux to Linux or Windows (didn't test other combinations, would likely have the same issue)
- Check Output dock / console

### Minimal reproduction project

[TestMono.zip](https://github.com/godotengine/godot/files/10445350/TestMono.zip)
Ref<CSharpScript> sqscr = p_resource;
	ERR_FAIL_COND_V(sqscr.is_null(), ERR_INVALID_PARAMETER);
	String source = sqscr->get_source_code();
#ifdef TOOLS_ENABLED
	if (!FileAccess::exists(p_path)) {
		// The file does not yet exist, let's assume the user just created this script. In such
		// cases we need to check whether the solution and csproj were already created or not.
		if (!_create_project_solution_if_needed()) {
			ERR_PRINT("C# project could not be created; cannot add file: '" + p_path + "'.");
		}
	}
#endif
	{
		Error err;
		Ref<FileAccess> file = FileAccess::open(p_path, FileAccess::WRITE, &err);
		ERR_FAIL_COND_V_MSG(err != OK, err, "Cannot save C# script file '" + p_path + "'.");
		file->store_string(source);
		if (file->get_error() != OK && file->get_error() != ERR_FILE_EOF) {
			return ERR_CANT_CREATE;
		}
	}
#ifdef TOOLS_ENABLED
	if (ScriptServer::is_reload_scripts_on_save_enabled()) {
		CSharpLanguage::get_singleton()->reload_tool_script(p_resource, false);
	}
#endif
	return OK;
}
void ResourceFormatSaverCSharpScript::get_recognized_extensions(const Ref<Resource> &p_resource, List<String> *p_extensions) const {