QA:Testcase Gnome Boxes box removal

Description

Removing boxes.

Setup

Have few boxes installed.

How to test

1. Navigate to boxes preview.

2. Click on "edit" icon.

3. Select box.

4. Click on "cross" icon and delete box.

5. Select "Undo" and "Cancel".

6. Delete box again and restart Boxes.

Expected Results

3. You can select box.

4. Message should appear.

5. You can select and run previously deleted box.

6. Removed box shoudn't appear after Boxes restart.