[SPMD][PoC] InputHandler for input sharding (#3963)
* [SPMD] Add at::Tensor sharding util & sharding tests.
* [SPMD] Add InputHandler for input sharding.
* [SPMD] Add PjRtShardedData & sharded data helper functions
* [SPMD] Add CreateTensorsData to shard & transfer tensor data
* [SPMD] Use shared_ptr for output_sharding_ in Node
* [SPMD] attach sharding annotatino to IR node only.
* Disable test_xla_sharding until we land all POC PRs
* [SPMD] Refactoring
