[IDC-1670] Better display of derived datasets in side panel. (#1962)

* WIP

* WIP

* WIP

* WIP

* Working click on seg.

* Load SEG if not loaded and set active.

* RTSTRUCT

* feat: 🎸 Display SEG and RTSTRUCT in side panel

* Throw error if dataset not available.

* Add delay in microscopy viewer e2e test.

* Add delay in microscopy viewer e2e test.

platform/viewer/src/components/ViewportGrid/ViewportGrid.js

@@ -80,6 +80,7 @@ const ViewportGrid = function(props) {
       // - When updating a panel, ensure that the currently enabled plugin
       // in the viewport is capable of rendering this display set. If not
       // then use the most capable available plugin
+
       const pluginName =
         !layout.plugin && displaySet && displaySet.plugin
           ? displaySet.plugin