Investigate methods to allow package to be imported in Jupyter Notebooks with Python<3.9

[kostaleonard]

Importing mlops in a Jupyter Notebook with Python<3.9 raises errors on the Python 3.9-style type annotations, which are not supported in previous versions. Python>=3.7 can bypass this by importing annotations from __future__. In a notebook environment, this does not seem to have any effect. What can we do to import mlops in a Jupyter Notebook with Python<3.9, short of reverting type annotations to the old style.