UI: added tb-toast to dashboard-page for displaying errors in fullscreen, singlepage modes etc

ui-ngx/src/app/modules/home/components/dashboard-page/dashboard-page.component.html

@@ -15,7 +15,7 @@
     limitations under the License.
 
 -->
-<div class="tb-dashboard-page mat-content" [ngClass]="{'mobile-app': isMobileApp && !isEdit}"
+<div class="tb-dashboard-page mat-content" [ngClass]="{'mobile-app': isMobileApp && !isEdit}" tb-toast
      fxFlex tb-fullscreen [fullscreenElement]="elRef.nativeElement" [fullscreen]="widgetEditMode || iframeMode || forceFullscreen || isFullscreen">
   <tb-hotkeys-cheatsheet #cheatSheetComponent></tb-hotkeys-cheatsheet>
   <section class="tb-dashboard-toolbar"