Update the encryption test for Jessie

With the updates that were done for 1.3, the encryption test is broken in Jessie. Maybe it would still have been broken without my changes.

(Although I didn’t know it at the time, some of the changes were actually working around #8928 (closed))

Feature Branch: kytv:bugfix/9046-update-encryption-feature-for-jessie

Original created by @kytv on 9046 (Redmine)

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