Adding missing type hints for BigBird model (#16555)
* added type hints for mbart tensorflow tf implementation
* Adding missing type hints for mBART model
Tensorflow Implementation model added with missing type hints
* Missing Type hints - correction
For TF model
* Code fixup using make quality tests
* Hint types - typo error
* make fix-copies and make fixup
* type hints
* updated files
* type hints update
* making dependent modesls coherent
* Type hints for BigBird
* removing typos
Co-authored-by: matt <rocketknight1@gmail.com>
