Add OpQuantizationConfig to schema v2 of Fusing class

[kkawa14]

Pull Request Description:

Adding fuse_op_quantization_config field to schema v2 of Fusing class
Adding unittests for Fusing class with schema v2

Checklist before requesting a review:

• I set the appropriate labels on the pull request.
• I have added/updated the release note draft (if necessary).
• I have updated the documentation to reflect my changes (if necessary).
• All function and files are well documented.
• All function and classes have type hints.
• There is a licenses in all file.
• The function and variable names are informative.
• I have checked for code duplications.
• I have added new unittest (if necessary).

[lior-dikstein]

Why is it necessary to check this? Doesn't Pydantic handle type validation automatically?

[kkawa14]

I couldn't fully understand the details of type validation in Pydantic.
I've confirmed that validation was working correctly with Pydantic, I removed the unnecessary validation code section.