Add pytest_rocm.yml workflow for ROCm testing
Create reusable workflow for ROCm pytest execution, following pytest_cuda.yml
pattern. Runs in ROCm team's GHCR containers with GPU device access, supports
configurable JAX versions (default 0.8.0), and uses custom jaxlib from GitHub
releases or PyPI.
Installs GitHub CLI for release downloads and executes run_pytest_rocm.sh
for test execution.
