Previously we sourced this script in tests/deploy.sh, but this was
recently changed. Following that change we lost the errexit setting,
meaning we ignore errors in init-runonce.

Adding errexit in the script itself means that all callers get error
handling.

Also log init-runonce output.

TrivialFix

Change-Id: I9b35bd5f0f76eec26ddd968d093a3a5fd55a7ce2