Juliabrot Fractal Overlay was stale

[FredKellerman]

For release v3.0.1 the 96b & 96b_mid overlays were not updated to the 2022.1 tools. This prevents the application from running. The 96b_deep image was correct, so until I rebuild the sd images for this release or the next upcoming version of PYNQ please use it instead of the default 96b overlay.

Otherwise if you rebuild the your own SD image from the master branch it will pickup the fixes.

Thanks for using PYNQ on Ultra96!