Missing class prop

That example in the docs doesn't seem to work. The `class` prop is not exported by the Svelte component.

```
  <script>
    import { SiSvelte } from "@icons-pack/svelte-simple-icons";
  </script>

  <SiSvelte class="myStyle" />

  <style>
    .myStyle {
      width: 35px;
      height: 35px;
    }
  </style>
```