When both the driver and executors run in the cluster, an ARMADA_AUTH_TOKEN defined only in the local config (e.g., config.sh) does not automatically propagate to the driver container after submission. As a result, the driver in cluster mode must obtain a token itself (via the signin binary) so it can talk to the Armada API and, transitively, to the executor pods.

Add logic to obtain a token using a sign-in binary.