[ONNX] Fix for constant folding: Slice, Added ReduceL1 and ReduceL2 (#35280)
Summary:
1- Added support for constant folding onnx::ReduceL1 and onnx::ReduceL2
2- Fixed constant folding for slice as onnx::Slice opset 11 supports negative axes and indices
3- Updated export of select opset 11
4- Separated test environment for test_utility_functions as environment variables could be overwritten by caffe2 quantization tests on CI
Pull Request resolved: https://github.com/pytorch/pytorch/pull/35280
Reviewed By: hl475
Differential Revision: D20626140
Pulled By: houseroad
fbshipit-source-id: 39667c7852eeaa97d9da23f53da52760d3670ecf
