Poc to use safetensors (#19175)

* Poc to use safetensors

* Typo

* Final version

* Add tests

* Save with the right name!

* Update tests/test_modeling_common.py

Co-authored-by: Julien Chaumond <julien@huggingface.co>

* Support for sharded checkpoints

* Test from Hub part 1

* Test from hub part 2

* Fix regular checkpoint sharding

* Bump for fixes

Co-authored-by: Julien Chaumond <julien@huggingface.co>

setup.py

@@ -148,6 +148,7 @@ _deps = [
     "rouge-score!=0.0.7,!=0.0.8,!=0.1,!=0.1.1",
     "sacrebleu>=1.4.12,<2.0.0",
     "sacremoses",
+    "safetensors>=0.2.1",
     "sagemaker>=2.31.0",
     "scikit-learn",
     "sentencepiece>=0.1.91,!=0.1.92",
@@ -300,6 +301,7 @@ extras["testing"] = (
         "protobuf",  # Can be removed once we can unpin protobuf
         "sacremoses",
         "rjieba",
+        "safetensors",
     )
     + extras["retrieval"]
     + extras["modelcreation"]