Optim-wip: Fix the Channel Attr notebook image download & metadata filename

[ProGamerGov]

GitHub's diff checker is reporting that the entire file changed, but I only changed a few lines of code.

• The image that this tutorial was using is no longer accessible as the hosting container for it was removed. I uploaded the image to GitHub and now the tutorial downloads it from GitHub instead.

• Previously the filename in the metadata was listed as "CaptumNotebookCells.ipynb" instead of "ChannelAttribution_OptimViz.ipynb".

[NarineK]

@ProGamerGov, do you mind pointing out here which lines did you change ?

[ProGamerGov]

@NarineK I changed the rendering to use batch targeting so that we didn't have to render each item in the list separately. I also changed the image download link, and updated the transform path names: optimviz -> opt, transform -> transforms.

[NarineK]

@ProGamerGov, do you mind looking into mypy checks and fixing them ?

[ProGamerGov]

@NarineK The MyPy error associated with the optim module is fixed in the optim-wip branch already

[NarineK]

@ProGamerGov , do you mind then rebasing from the optim-wip branch so that the errors get fixed ?

[ProGamerGov]

@NarineK Okay, I've done that and the error is no longer present, There will hopefully be no errors once the fixes from #935 are in play

[NarineK]

Thank you, @ProGamerGov! I left comments in #935