Delete volumes after each scenario

Initial review passed (see “Please review’n’merge test/keep-volumes-tag” thread on tails-dev), needs to be tested and merged.

Also, it is based on the test/reorg branch (#6543 (closed)), so either it should wait for that other branch to be merged, or its single commit should be cherry-picked on top of the current development head.

Feature Branch: test/keep-volumes-tag

Related issues

• Related to #5978 (closed)
• Blocked by #6399 (closed)

Original created by @intrigeri on 6544 (Redmine)