Add functional tests for GPG encryption

[jneo8]

There are no functional tests for the GPG encryption feature. This has led to bugs like LP#1912580, where the feature does not work properly.

Ideally a functional test would create a gpg keypair, configure the charm for functional gpg encryption and validate that the backups are created and can actually be decrypted with the relevant private key.

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Imported from Launchpad using lp2gh.

• date created: 2021-01-21T23:13:46Z

• owner: jfguedez

• assignee: None

• the launchpad url

[jneo8]

(by xavpaice)
To close this, we will need a functest that actually runs the CLI for duplicity in order to validate that the CLI is parsed correctly.