Add support for ShimmeredDetailsList component

[kyle-power]

Referring to the Shimmer() progress indicator: https://developer.microsoft.com/en-us/fluentui#/controls/web/shimmer
section "Shimmered DetailsList simulating loading data asynchronously"

<ShimmeredDetailsList
  setKey="items"
  items={items || []}
  columns={shimmerColumns}
  selectionMode={SelectionMode.none}
  onRenderItemColumn={onRenderItemColumn}
  enableShimmer={!items}
  ariaLabelForShimmer="Content is being fetched"
  ariaLabelForGrid="Item details"
  listProps={shimmeredDetailsListProps}
/>

[kamilzyla]

Thanks @kyle-power, we'll look into adding this in a future release!