Fix docker build failure in nighlty

[dhuangnm]

Fixed two issues:

1. Trigger nm pypi update workflow in stratus automatically after wheels are uploaded to GCP.
2. Docker build step should only run after the upload step is finished successfully.

An example run from nm-vllm: https://github.com/neuralmagic/nm-vllm/actions/runs/9810788569

which triggers stratus nm pypi update workflow run: https://github.com/neuralmagic/stratus/actions/runs/9810806638

[andy-neuma]

thanks