Add StableLM (#28810)

* Add `StableLM`

* fix(model): re-create from `huggingface-cli add-new-model-like persimmon`

* fix: re-add changes to address comments

* fix(readme): add links to paper

* fix(tokenization_auto): remove `GPTNeoXTokenizerFastFast` ref

* fix(tests): re-add `@slow` decorator to integration tests

* fix(tests): import slow...

* fix(readme_hd): remove whitespace edit

* fix(tokenizer): auto tokenizer tuple

* skip doctests for `modeling_stablelm`

utils/not_doctested.txt

@@ -804,6 +804,7 @@ src/transformers/models/speecht5/number_normalizer.py
 src/transformers/models/splinter/configuration_splinter.py
 src/transformers/models/splinter/modeling_splinter.py
 src/transformers/models/squeezebert/modeling_squeezebert.py
+src/transformers/models/stablelm/modeling_stablelm.py
 src/transformers/models/swiftformer/configuration_swiftformer.py
 src/transformers/models/swiftformer/convert_swiftformer_original_to_hf.py
 src/transformers/models/swiftformer/modeling_swiftformer.py