How to wrap views-view-fields.html.twig with html container element?
Option 1

You can by copying (the entire code) from core views-view.html and paste it in your theme's template folder and rename it views-view--[view-name].html.twig and then add your class to this template file.

replace {{ rows }} with 

&lt;div class="slider-article"&gt;
{{ rows }}
&lt;/div&gt;


Option 2

Copy from core views-view-fields and paste it in your theme's template folder, rename it views-view-fields--[view-name].html.twig

Then add your div with class before {% for field in fields -%} and add close tag after {%- endfor %}

Option 3 (maybe)

You can add it via the Views UI by clicking on "None". But this will add the wrapper to the entire view, which you may not want.