Add TF GPTNeoX 
### Feature request

Add the GPTNeoX model in TensorFlow.

### Motivation

Having GPTNeoX in TensorFlow would benefit the community.

### Your contribution

@gante is it possible to assign this to me?  
(@Rocketknight1 FYI)<|||||>@JIPHF If you're happy to make a PR for this, then please do! Let us know if you need any help with that.<|||||>This issue has been automatically marked as stale because it has not had recent activity. If you think this still needs to be addressed please comment on this thread.

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