Model does not have a sagemaker_session property

**PySDK Version**
- [ ] PySDK V2 (2.x)
- [ X] PySDK V3 (3.x)

**Describe the bug**
A clear and concise description of what the bug is.

ModelStep expects the Model class to have a `sagemaker_session` attribute but the spec does not allow it

**To reproduce**

Provide a Model instance as the `model` argument of the register model step arguments

**Expected behavior**
ModelStep can be instantiated with a repack step

**Screenshots or logs**
If applicable, add screenshots or logs to help explain your problem.

**System information**
A description of your system. Please provide:
- **SageMaker Python SDK version**: 3
- **Framework name (eg. PyTorch) or algorithm (eg. KMeans)**: SKLearn
- **Framework version**: 1.4.2
- **Python version**: 3.11
- **CPU or GPU**: CPU
- **Custom Docker image (Y/N)**: N

**Additional context**
Add any other context about the problem here.

Start by locating ModelStep, the Model class, and the register model step arguments involved in the reported reproduction. Check how the repack step accesses model.sagemaker_session and how the model specification handles that attribute; done means a Model instance can instantiate ModelStep with a repack step.

Written by the indexing model from the issue text.