Instead of getting users to run a tree_map over gdas, etc and run asyncio.run, absorb those APIs into the gda serde library.
Instead of getting users to run a tree_map over gdas, etc and run asyncio.run, absorb those APIs into the gda serde library.

PiperOrigin-RevId: 424923960

tensorflow/lingvo,tensorflow/lingvo,tensorflow/lingvo,tensorflow/lingvo