testflake: mail_crypt.rb:94:in `Integer': invalid value for Integer(): ""
The following looks like a test-flake -discovered in a CI run for !45 (merged):
https://code.immerda.ch/immerda/apps/iapi/-/jobs/15222
/var/lib/gitlab-runner/runners/container-immer13-14.glei.ch/builds/immerda/apps/iapi/lib/iapi/utils/mail_crypt.rb:94:in `Integer': invalid value for Integer(): "" (ArgumentError)
from /var/lib/gitlab-runner/runners/container-immer13-14.glei.ch/builds/immerda/apps/iapi/lib/iapi/utils/mail_crypt.rb:94:in `initialize'
from /var/lib/gitlab-runner/runners/container-immer13-14.glei.ch/builds/immerda/apps/iapi/lib/iapi/utils/mail_crypt.rb:125:in `new'
from /var/lib/gitlab-runner/runners/container-immer13-14.glei.ch/builds/immerda/apps/iapi/lib/iapi/utils/mail_crypt.rb:125:in `deserialize'
from /var/lib/gitlab-runner/runners/container-immer13-14.glei.ch/builds/immerda/apps/iapi/lib/iapi/utils/mail_crypt.rb:284:in `authenticate'
from /var/lib/gitlab-runner/runners/container-immer13-14.glei.ch/builds/immerda/apps/iapi/bin/mailcrypt-cli.rb:242:in `<main>'