Include some markup in consolidated app

[tiagosousagarcia]

Describe the bug
Fix the current procedure for consolidating sections from 1609 that have internal markup (such as notes). Currently, only the text is kept, but this needs to be marked up in some way to differentiate it from the main body of the text if necessary.

To Reproduce
Steps to reproduce the behavior:

1. Create two milestones in 1609 that have some markup in between them (i.e., a note, a highlight)
2. Create an app in 1623 that references those two milestones
3. Run automate_variation.py
4. Observe the results in the newly created app

Expected behavior
Some markup must be retained, especially if it separates a portion of the text from the main body of the text