[`StableLm`] Add QK normalization and Parallel Residual Support
Author: jon-tow
Pull request: yes
Labels: name: New model

# What does this PR do?

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This PR adds support for the latest Stable LM 2 architecture that requires QK normalization and parallel residual layers.

## Before submitting
- [ ] This PR fixes a typo or improves the docs (you can dismiss the other checks if that's the case).
- [x] Did you read the [contributor guideline](https://github.com/huggingface/transformers/blob/main/CONTRIBUTING.md#create-a-pull-request),
      Pull Request section?
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      [here are tips on formatting docstrings](https://github.com/huggingface/transformers/tree/main/docs#writing-source-documentation).
- [x] Did you write any new necessary tests?


## Who can review?

cc @ArthurZucker 

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Models:

- text models: @ArthurZucker and @younesbelkada
- vision models: @amyeroberts
- speech models: @sanchit-gandhi
- graph models: @clefourrier

Library:

- flax: @sanchit-gandhi
- generate: @gante
- pipelines: @Narsil
- tensorflow: @gante and @Rocketknight1
- tokenizers: @ArthurZucker
- trainer: @muellerzr and @pacman100

Integrations:

- deepspeed: HF Trainer/Accelerate: @pacman100
- ray/raytune: @richardliaw, @amogkam
- Big Model Inference: @SunMarc
- quantization (bitsandbytes, autogpt): @SunMarc and @younesbelkada

Documentation: @stevhliu and @MKhalusova

HF projects:

- accelerate: [different repo](https://github.com/huggingface/accelerate)
- datasets: [different repo](https://github.com/huggingface/datasets)
- diffusers: [different repo](https://github.com/huggingface/diffusers)
- rust tokenizers: [different repo](https://github.com/huggingface/tokenizers)

Maintained examples (not research project or legacy):

- Flax: @sanchit-gandhi
- PyTorch: See Models above and tag the person corresponding to the modality of the example.
- TensorFlow: @Rocketknight1

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Comments:
Could you add 1 generation test! 🤗 

The docs for this PR live [here](https://moon-ci-docs.huggingface.co/docs/transformers/pr_29745). All of your documentation changes will be reflected on that endpoint. The docs are available until 30 days after the last update.

>  Could you add 1 generation test! 🤗

Added! I've further trained the tiny random test model ([stabilityai/tiny-random-stablelm-2](https://huggingface.co/stabilityai/tiny-random-stablelm-2)) on a few billion tokens of [cosmopedia](https://huggingface.co/datasets/HuggingFaceTB/cosmopedia) so that failed checks are easily detectable as opposed to verifying against jumbled sample tokens/text.

Let me know if you need anything else. Thanks for the review 🙏