class ActionView::Renderer

so in such cases, we just wrap them in an array.
Note that partials are not supported to be rendered with streaming,

a streaming body that renders the template piece by piece.
Render but returns a valid Rack body. If fibers are defined, we return

def render_body(context, options)
  if options.key?(:partial)
    [render_partial(context, options)]
  else
    StreamingTemplateRenderer.new(@lookup_context).render(context, options)
  end
end