Add type hints for tf models final batch (#25883)
* Add missing type hints and consistency to `RegNet` models
* Add missing type hints and consistency to `TFSamModel`
* Add missing type hints to `TFSegformerDecodeHead`
* Add missing type hints and consistency to `TransfoXL` family models
* Add missing type hints and consistency to `TFWav2Vec2ForSequenceClassification`
* Add type hints to `TFXLMModel`
* Fix linter
* Revert the type hints for `RegNet` to python 3.8 compliant
* Remove the redundant np.ndarray type hint.
