[BUG] Jupyter Caching gifs with Same Name

Describe the bug

See discussion here: https://julialang.zulipchat.com/#narrow/stream/253420-javis.2Ejl/topic/Javis.20Jupyter.20Viewer.20Bug/near/244873375

To Reproduce

1. Julia Version (i.e. output of julia -v): 1.6.0

2. Operating system (Mac, Linux, Windows): Fedora 34 (linux)

3. Javis version (i.e output of ] status Javis in the REPL): v0.5.2

4. Minimum working code example that led to bug: https://github.com/mforets/escritoire/blob/8cd6c5a7a3a8f28a25d37bce4757c3dd5b2ba35d/2021/Week27/Javis_Test_1.ipynb

Expected Behavior and Actual Behavior

Object colors were not updated between running of Jupyter cells when animation was saved to previously rendered animation with the same name.

Additional context

See @mforets notebook here for the code that was causing this behavior https://github.com/mforets/escritoire/blob/8cd6c5a7a3a8f28a25d37bce4757c3dd5b2ba35d/2021/Week27/Javis_Test_1.ipynb