Description of problem:

The "rhods-groups-config" ConfigMap seems to accept multiple groups as RHODS admins (it asks for "admin_groups"). Since it is true for user groups (non-admin ones) as instructed by the Documentation, it is reasonable for the user to think it should be possible for the admins too. But, the dashboard triggers an error if more groups are specified (comma-separated list) and no one is recognized as admin when logging in. 

While, if you ignore the error message and continue with setting multiple groups as admins, JH will accept this configuration. 

So this bug is to fill this consistency gap, by either:

1. fix the dashboard logic to accept multiple groups
2. fix the documentation by specifying it is not possible

In the second option, JH may need a fix too.

Even though the new UI https://issues.redhat.com/browse/RHODS-2740 will be soon implemented, this is something which need to be addressed, because it will always be possible to change the config map. Besides, the ambiguity in the naming will remain.

Prerequisites (if any, like setup, operators/versions):

Steps to Reproduce

1. set "rhods-groups-config to use multiple admin groups (e.g., 

   admin_groups: dedicated-admins,rhods-users

1. check Dashboard logs. You might see this error in RHODS v1.12

   Failed to get groups: HttpError: HTTP request failed

1. Access dashboard using any users from both the admin groups (no one will be recognized as admin)
2. rollout JH
3. Access JH using any users from both the admin groups (all those users will be recognized as admin) 

Actual results:

• no one will be recognized as admin in Dashboard
• all those users from the multiple admin groups will be recognized as admins in JH

Expected results:

1. The dashboard should allow having multiple groups separated by commas in `admin_groups`.
2. The dashboard should not allow having `system:authenticated` in `admin_groups`.
3. All this behaviour will be implemented in RHODS-2740

Reproducibility (Always/Intermittent/Only Once):

Always

Build Details:

RHODS v1.12

Workaround:

Additional info: