[Data] Improve fractional CPU/GPU formatting (ray-project#45673)

This makes progress bar look nicer when fractional resources are used.

Signed-off-by: Daniel Kłobuszewski <daniel.klobuszewski@gmail.com>

Author: x13n

python/ray/data/_internal/execution/streaming_executor.py

@@ -331,8 +331,8 @@ def _report_current_usage(self) -> None:
         limits = self._resource_manager.get_global_limits()
         resources_status = (
             "Running: "
-            f"{cur_usage.cpu}/{limits.cpu} CPU, "
-            f"{cur_usage.gpu}/{limits.gpu} GPU, "
+            f"{cur_usage.cpu:.4g}/{limits.cpu:.4g} CPU, "
+            f"{cur_usage.gpu:.4g}/{limits.gpu:.4g} GPU, "
             f"{cur_usage.object_store_memory_str()}/"
             f"{limits.object_store_memory_str()} object_store_memory"
         )