[Canvas] Fixes Workpad fullscreen due to max-width limitation (#47371) (#47576)

* Allow row to extend past viewport width to allow proper fullscreen canvas view

* Added note

x-pack/legacy/plugins/canvas/public/components/fullscreen/fullscreen.scss

@@ -40,6 +40,11 @@ body.canvas-isFullscreen { // sass-lint:disable-line no-qualifying-elements
     }
   }
 
+  .canvasLayout__rows {
+    // this is critical for the row to expand outside of the viewport for proper fullscreen sizing
+    max-width: none;
+  }
+
   .canvasLayout__rows,
   .canvasLayout__cols {
     align-items: center;