CloudFormation::Init::Packages supports EOLd Python packages only

Hello

When using CloudFormation::Init to setup EC2 instances, we can not use the packages: stanza to install python packages for python3. As is well known, [python 2 was sunset more than 18 months ago](https://www.python.org/doc/sunset-python-2/).

Currently, we have to use the commands: stanza in order to install python3 packages, which seems a bit...um.

Start by reviewing the CloudFormation::Init packages stanza and how it differs from the commands stanza for Python installation. The issue does not name repository files or tests, so locating the implementation and validation path will require project familiarity. Done means packages supports installing Python 3 packages without requiring commands.

Written by the indexing model from the issue text.