Consume ONNX 1.12.1 to prevent vulnerability issue while loading external file

[jcwchen]

Description:
Consume ONNX 1.12.1 to prevent vulnerability issue while loading external file. That rel-1.12.1 branch uses the base of rel-1.12.0 with 2 additional PRs: onnx/onnx#4400 and onnx/onnx#4470.

Motivation and Context
To prevent vulnerability issue: ONNX checker load external file outside the directory, ONNX 1.12.1 will include these 2 PRs:

• Do not allow to read tensor's external_data outside the model directory onnx/onnx#4400
• Use filesystem to load filename to prevent encoding issues on Windows onnx/onnx#4470

[snnn]

Thank you!