Cluster admin does not get RHODS Admin access if it's the only user in the cluster

Description of problem:

It looks like when the cluster admin is the only user present in the cluster, it doesn't get the RHODS Admin access automatically. 

The dashboard pod reports these lines of error about rolebindings:

{"level":50,"time":1664785629417,"pid":108,"hostname":"rhods-dashboard-59bb5c9d89-6kb2f","msg":"Failed
 to list rolebindings for user, Failed to list groups filtered by 
username."}{"level":50,"time":1664785629436,"pid":108,"hostname":"rhods-dashboard-59bb5c9d89-6kb2f","msg":"Failed
 to list rolebindings for user, Failed to list groups filtered by 
username."}
...

As soon as we created more users, it got the permissions and the logs stopped to show those errors about role binding.

Pull Request:

https://github.com/opendatahub-io/odh-dashboard/pull/725

Steps to Reproduce

1. Create a cluster (reproduced on OSD)
2. Create only one user with cluster admin permissions (no other users in the cluster)
3. Log in RHODS Dashboard using the cluster admin
4. Check if the user can access the "Settings" section of RHODS
5. create new users
6. Check point 4) once again

Actual results:

• Cluster admin doesn't get RHODS Admin access if it is the only user present in the cluster
• dashboard logs keep reporting an error about fetching role bindings

Expected results:

• cluster admin always get RHODS Admin access
• dashboard does not report any error about fetching rolebinding

Reproducibility (Always/Intermittent/Only Once):

Tested once on a fresh OSD cluster for now. 

Build Details:

RHODS v1.17.0-9

Workaround:

• create more users
• (To be Verified) granting cluster admin permissions to the single user instead of group (RHODS-5100). This is not verified 

Additional info:

• May be related to https://issues.redhat.com/browse/RHODS-5100
• the cluster admin user has been defined by granting ClusterAdmins to a user group