[Python] Add Python wrapper for VariableShapeTensor

[rok]

Describe the enhancement requested

Once C++ implementation of VariableShapeTensor is complete (#38007) we want a Python wrapper for it.

Component(s)

Python

[github-actions]

This issue has been marked as stale because it has had no activity in the past 365 days. Please remove the stale label or comment below, or this issue will be closed in 14 days. If this improvement is still desired but has no current owner, please add the 'Status: needs champion' label.