[Task] Expand OAuth token scope for multiple namespaces

[ebaron]

Cryostat still requests an OAuth token scoped to the namespace it's installed in. With multi-namespace support, Cryostat will need a scoped token with role scopes for each of the configured target namespaces. If we add cluster-wide support, we can use the * syntax: https://docs.openshift.com/container-platform/4.12/authentication/tokens-scoping.html#scoping-tokens-role-scope_configuring-internal-oauth