* Feature/vit support (#4182)
* [shardformer] added tests
* [shardformer] vit test finish and support
* fix attention dropout
* support base vit pipeline
* support vit downstream model
* fix vit shard test
* modify hidden states return type
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Co-authored-by: Kun Lin <81014421+klhhhhh@users.noreply.github.com>
* complete policy for T5Model & T5ForConditionalGeneration
* modify function signature in forwards
* add forward for T5model
* add forward for T5ForConditionalGeneration
* fix a bug
* fix hidden_states transporting in decoder
* fix the passing of encoder_outputs