Fixed a couple of errors on import/export spotted in production

Fixes https://gitlab.com/gitlab-org/gitlab-ce/issues/18828 and https://gitlab.com/gitlab-org/gitlab-ce/issues/18829

A couple of tiny bugs spotted after deploying in prod

Added 1 commit:

• d5b3a266 - use rails root join

Reassigned to @rymai

@rymai quick one to review! thanks

Status changed to merged

mentioned in commit 44b8b77e

Thanks James!

Added ~149423 label

Removed ~149423 label

Picked into 8-9-stable, will be in RC8.

mentioned in commit 95aaf66e