add ONNX support for BLOOM (#17961)

* add onnx support for BLOOM

* use TYPE_CHECKING for type annotations

* fix past_shape for bloom (different from gpt2)

* use logical_or instead of `+` for onnx support

* bigger `atol_for_validation` for larger bloom models

* copied -> taken because it's no longer an exact copy

* remove "copied from" comment

Co-authored-by: Sylvain Gugger <35901082+sgugger@users.noreply.github.com>

Co-authored-by: Sylvain Gugger <35901082+sgugger@users.noreply.github.com>

tests/onnx/test_onnx_v2.py

@@ -205,6 +205,7 @@ PYTORCH_EXPORT_MODELS = {
 }
 
 PYTORCH_EXPORT_WITH_PAST_MODELS = {
+    ("bloom", "bigscience/bloom-350m"),
     ("gpt2", "gpt2"),
     ("gpt-neo", "EleutherAI/gpt-neo-125M"),
 }