Update visualizing-mri-volume-slices.md

[LeoMcBills]

I removed a trailing whitespace at the end of the file

[empet]

I think this example should be removed because the implementation is particular and can't be used for another image stack. This code was the first attempt to animate slices, later generalized here: https://nbviewer.org/github/empet/Animating-MRI-scans/blob/master/scanning-the-head-classic.ipynb

[gvwilson]

@LiamConnors what do you think about @empet 's suggestion?

[LiamConnors]

@empet and @gvwilson, yes that makes sense to me to just remove this page.

[gvwilson]

:+1: delete it please

[LiamConnors]

We've removed this page in another PR, so closing this one out.

[LeoMcBills]

Alright @LiamConnors, thank you.