Onboard the VictoriaLogs query UI at https://vlogs.unkin.net behind
oauth2-proxy, gated on akP-vlogs-admin.
- add config/providers_oauth2/vlogs.yaml reading its client_secret from
kv/kubernetes/namespace/logging/default/vlogs-oauth-credentials
- add permission group akP-vlogs-admin bound to the vlogs application
- nest akP-vlogs-admin under akR-global-admin