Serialize NamedDataStoreOutput into PTD. (#9758)

Update PTD serialization to account for blobs from the NamedDataStoreOutput.

Something we can do in the future is to consolidate tensors (that go through the emitter) and blobs (that come from the NamedDataStore).

Differential Revision: [D70939807](https://our.internmc.facebook.com/intern/diff/D70939807/)