Several of the file examples are missing online and in generated PDF

[cchouina]

I finally got to reading the Mission Modeling PDF (from https://github.com/NASA-AMMOS/aerie-docs/actions/runs/7716737111) and noticed that several of the file examples are missing. When I look at the online documentation, it looks like they are broken there too:
https://nasa-ammos.github.io/aerie-docs/mission-modeling/introduction/

[dandelany]

This was fixed in the web documentation, eg. it now works here:

https://nasa-ammos.github.io/aerie-docs/mission-modeling/introduction/

However, it is unfortunately still an issue in the generated PDF docs and I have not yet found a fix - the PDF generator script does not seem to wait for external example files to be loaded.