to support 3 dim attention mask in tf version
Author: BruceJust
Pull request: yes
Labels: name: TensorFlow

support 3 dim attention mask

# What does this PR do?

to support 3 dim attention mask in tf version

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Fixes # (issue)


## Before submitting
- [ ] This PR fixes a typo or improves the docs (you can dismiss the other checks if that's the case).
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- [ ] Did you write any new necessary tests?


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