Model client validation css styles not work well with @Html.EditorFor

### Describe the bug

If use `@Html.EditorFor` with the expression for a property, client-side validation will display error message with wrong css style.


***The `class` attribute has no value***


### To Reproduce

```
@for (var i = 0; i < Model.TestChildModels.Count; i++)
{
@Html.EditorFor(model => model.TestChildModels[i])
}
```

_**_EditorTemplate/TestChildModel.cshtml_**_

```
@model TestChildModel

```
**The workaround I am using now**

_add following code snippet in `site.css`_

```
span.field-validation-error span {
color: red;
}
```

### Further technical details
- ASP.NET Core version 5.0