Implement Keycloak Integration With Headlamp

Feature Request

Implement Keycloak Integration With Headlamp

Why

Headlamp currently provides Kubernetes token authentication. Work done under this issue: #41 brought in the ability to have user-defined RBAC -- tied to service accounts / tokens.

See comments in this thread for some details: !68 (comment 3895719)

Proposed Solution

We should investigate tying headlamp into Keycloak where we can leverage SSO with different accounts and RBAC. See if it's possible and if so, provide the ability to configure this integration.