This one was actually pretty easy to solve, but was interesting anyway.
Developing locally I was OK using http requests for my script files as my local server has now issues with using either http or https for requests. However, App Engine has other ideas. In my scripts file I was including the below reference:
This worked no problem on my machine, but when I published to Google App Engine I saw the below:
Once I changed the script to use HTTPS:
Then I was presented with what I wanted to see: