Fix gfz development multiple client ids

Uses the development config for the backend. Same as on the old "development" deployment on port 5000. Therfor I add an environment variable to the job (not docker-compose!) to handle this option.

Apparently we need to set it to allow multiple oidc client ids, as production does not allow this following this comment:

# For production we only want to have one audience that should be allowed

https://gitlab.hzdr.de/hub-terra/sms/backend/-/blob/master/app/project/config.py#L124

@marc.hanisch I already deployed this fix from this branch, so you can work without the workaround. I keep this merge request open until tomorrow (so you can have a look into it if you want) and will merge it then.