Make the confirmation more scary when reinstalling a USB stick that has a Persistent Storage
Right now, the experience when upgrading and reinstalling from Tails Installer is too similar:

vs.

We could instead:
- Remove the confirmation dialog when upgrading.
- Make the confirmation dialog more scary when reinstalling:
* Without Persistent Storage on the target USB stick:
**Confirm the target USB stick**
⚠
15.5 GB TOSHIBA TransMemory device (/dev/sda1)
All data on this USB stick will be lost.
[Cancel] [Delete All Data and Install]
* With a Persistent Storage on the target USB stick:
**Confirm the target USB stick**
⚠
15.5 GB TOSHIBA TransMemory device (/dev/sda1)
The Persistent Storage on this USB stick will be lost.
[Cancel] [Delete Persistent Storage and Reinstall]
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