Manually execute database encryption

With VIMP 4.1.1 sensitive config database fields are being encrypted. Encryption will not be executed automatically with an update, but has to be performed manually once.

To encrypt those config database fields, execute the following command once after you upgraded from VIMP <=4.1.0 to a version >=4.1.1:

./symfony framework:aesencrypt

You don't have to do anything with a new installation or a subsequent update to a newer version.