Move splitting ops from default to qpreserving configs in TPCv4.

[elad-c]

Pull Request Description:

This PR moves splitting ops (e.g. split, unstack and slice) to a "qpreserving" opset. This opset disables activation quantiztion, enables quantization preserving and enables input & output tensors to be 16 bits.
This PR is compatible with the op definitions in the converter release 3.16.

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).