e2e: use -detach mode when registering jobs with cli (#10877)
e2e: use -detach mode when registering jobs with cli (#10877)

Pick up 15d39f0dee but for RegisterFromJobspec:

>  This PR changes the e2e helper thingy to set -detach option
>  when registering a job with the CLI instead of the API. This is
>  necessary for jobs which never become healthy, as the deployment
>  never finishes for failing jobs and the command never returns,
>  causing the test to timeout after 10 minutes.

This case occurs in TestVaultSecrets
dvusboy/nomad,dvusboy/nomad,hashicorp/nomad,hashicorp/nomad,dvusboy/nomad,dvusboy/nomad,hashicorp/nomad,dvusboy/nomad,hashicorp/nomad,hashicorp/nomad,hashicorp/nomad,dvusboy/nomad,dvusboy/nomad