Warn user before wiping the database (connection wizard)

[thiswillbeyourgithub]

Issue details

Related to #1261 (comment)

Actual behaviour

• Re running the connection wizard deleted the local database.

Expected behaviour

• Running the connection wizard should always warn you before wiping a database.

Steps to reproduce the issue

1. run the connection wizard
2. notice that your db is gone

Environment details

• wallabag app version: 2.4.3
• wallabag app installation source (e.g. Gplay, F-Droid, manual): FDroid
• wallabag server version: 2.4.3

[di72nn]

Sorry for the inconvenience. That is indeed a very real issue that somehow hasn't been brought up before.

In other situations I really tried to take extra caution keeping the added links safe.