Run Android release job on ephemeral runners (#10190)

To summary the discussion with @kirklandsign, only repository secrets
are accessible in a Nova linux job. However, GitHub warns against using
such secrets on persistent self-hosted runners
https://docs.github.com/en/actions/security-for-github-actions/security-guides/security-hardening-for-github-actions#hardening-for-self-hosted-runners.
In this case, it's important to use a fresh ephemeral runner instead to
make sure that nothing on the runner could steal these secrets.

### Testing

https://github.com/pytorch/executorch/actions/runs/14465234621