fix: add deprecated decorator to get_memory_usage

Author: hoel-bagard

stubs/tensorflow/tensorflow/config/experimental.pyi

@@ -1,3 +1,4 @@
+import typing_extensions
 from _typeshed import Incomplete
 from typing import TypedDict
 
@@ -9,6 +10,7 @@ class _MemoryInfo(TypedDict):
 
 def get_memory_info(device: str) -> _MemoryInfo: ...
 def reset_memory_stats(device: str) -> None: ...
+@typing_extensions.deprecated("This function is deprecated in favor of tf.config.experimental.get_memory_info")
 def get_memory_usage(device: PhysicalDevice) -> int: ...
 def get_memory_growth(device: PhysicalDevice) -> bool: ...
 def set_memory_growth(device: PhysicalDevice, enable: bool) -> None: ...