Port users to use torchx.specs.named_resource instead of internal fb module

Summary: Port user code to use ``torchx.specs.named_resource``

Reviewed By: kiukchung

Differential Revision: D29067087

fbshipit-source-id: 7bd308cbb8489a276a76eb5503a62e000a6cf181

Author: aivanou

torchx/specs/__init__.py

@@ -8,6 +8,8 @@
 from .api import *  # noqa: F401 F403
 from torchx.util.entrypoints import load
 
+GiB: int = 1024
+
 
 def named_resource(resource: str) -> Resource:
     """