gitlab-runner register --non-interactive doesn't care of --config args

Hello,

On gitlab-runner 9.5.0 i tried the command :

gitlab-runner register --non-interactive --url <https://my-personnal-host> --registration-token <my_registration_token> --executor docker --docker-image <myPersonnalRegistry> --name Test_test --docker-pull-policy always --locked False --run-untagged False --docker-privileged false --token 23f574bd4ae734bc04c1f143db9962 --limit 0 --tag-list test --config /tmp/runner-2b546663-94b4-4a0e-a305-b311962925ac.tmp

But it still write to the /etc/gitlab-runner/config.toml The file /tmp/runner-2b546663-94b4-4a0e-a305-b311962925ac.tmp was not created

As this option figure in gitlab-runner register --help i was thinking than the command should write in the file mentionned in this argument