Don't raise exception for successful `verdi archive import -n`

[GeigerJ2]

When doing a dry-run of an archive import, the import_archive function raises the ImportTestRun('test run complete') exception, resulting in a user-facing Critical: output. Is there any particular reason for this behavior, rather than just a Report: that the dry-run is done?

Relevant code here: https://github.com/aiidateam/aiida-core/blob/be0db3cc49506294ae1845b6e746e40cd76f39a9/src/aiida/cmdline/commands/cmd_archive.py#L516-L525

https://github.com/aiidateam/aiida-core/blob/be0db3cc49506294ae1845b6e746e40cd76f39a9/src/aiida/tools/archive/imports.py#L198-L200