When trying to remove a service account from RBAC group, a "service-account-" is still needed in the request (example):
https://console.stage.redhat.com/api/rbac/v1/groups/40aed703-5532-4ad5-8f17-b8178282ba57/principals/?service-accounts=service-account-1fe84010-6b7b-4b39-8fb0-024cc63b0d07
Without the prefix (https://console.stage.redhat.com/api/rbac/v1/groups/40aed703-5532-4ad5-8f17-b8178282ba57/principals/?service-accounts=1fe84010-6b7b-4b39-8fb0-024cc63b0d07), the request returns 404Expected state - remove the prefix check

Let's also update the "service-accounts" API param OpenApi specs to say "A comma separated list of client IDs for service accounts to remove from group" rather than "A comma separated list of usernames for service accounts to remove from group"