[editor] Fix tab to create new page

This hack allows the page tabs to have a pseudo tab to create a new 
page.
This tab is disabled so the user can not change to it, but is still 
clickable.

projects/editor/src/app/components/unit-view/unit-view.component.css

@@ -88,3 +88,7 @@ aspect-page-canvas {
   right: 15%;
   bottom: 15%;
 }
+
+:host ::ng-deep div.mat-mdc-tab * {
+  pointer-events: auto;
+}