adjust copybara rules and remove jax.device assertion

PiperOrigin-RevId: 863427436

Author: Google-ML-Automation

src/maxtext/examples/shardings.py

@@ -123,7 +123,6 @@ def simple_timeit(f, tries=5, verbose=True):
   devices = jax.devices()
   num_devices = len(devices)
   print(f"Devices: {devices} (num_devices: {num_devices})")
-  assert len(devices) > 1, "You must have at least two devices"
 
   # Assert that we have correct inputs of sharding that fit the number of chips
   assert (