Move tutorials from Day 4 capsule to databook

[ ] Optotagging - this might be able to be combined with content for VCN and CTLUT
[ ] Receptive fields - again, might be combine with VCN. See how similar
[ ] Visual Behavior Neuropixels - see if any of this isn't already represented in the databook
[ ] VBN get unit CCF - ideally we want this in the databook. There might be a reason so find out if there's a technical reason it's not already there.

AllenSWDB / allenswdb.github.io