[CI] Run torch-latest only on AWS (#8825)
(#8824 should be merged first)
In #8770, we pinned Modal sandbox placement to Oracle Cloud
Infrastructure (OCI), where a working NVIDIA driver version was still
available, to avoid the CUDA/NCCL failures seen on other Modal hosts.
The affected driver has since been rolled out to OCI as well, so this
workaround no longer provides a reliable path for our multi-GPU CI
workload. Modal has identified the issue and is working on a fix.
This PR temporarily disables Modal until the driver issue is resolved,
and run the required torch-latest workflow entirely on the existing AWS
backend.
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Signed-off-by: Masahiro Tanaka <tanaka.masahiro@gmail.com>
