Add guard clause to prevent module execution on import

cyclops/evaluate/metrics/experimental/distributed_backends/torch_distributed.py

@@ -95,3 +95,7 @@ def all_gather(self, data: torch.Tensor) -> List[torch.Tensor]:  # type: ignore[
             slice_param = [slice(dim_size) for dim_size in item_size]
             gathered_data[idx] = gathered_data[idx][slice_param]
         return gathered_data
+
+
+if __name__ == "__main__":  # prevent execution of module on import
+    pass