remove broken/unnecessary calls to EBI for PDB structure images

[andrewsu]

On the Chlambase page for CTL0245, we make requests to these three URLs which return 404 errors:

https://www.ebi.ac.uk/pdbe/static/entry/_deposited_chain_front_image-800x800.png
https://www.ebi.ac.uk/pdbe/static/entry/_deposited_chain_side_image-800x800.png
https://www.ebi.ac.uk/pdbe/static/entry/_deposited_chain_top_image-800x800.png

CTL0245 has no PDB entries.

On CT_622 which does have a PDB entry, we make those three calls and these three (which are the ones that actually show up on the page):

https://www.ebi.ac.uk/pdbe/static/entry/5ue0_deposited_chain_front_image-800x800.png
https://www.ebi.ac.uk/pdbe/static/entry/5ue0_deposited_chain_front_image-800x800.png
https://www.ebi.ac.uk/pdbe/static/entry/5ue0_deposited_chain_top_image-800x800.png

So it appears that the first three links listed above are being called unnecessarily. Would be great to figure out how to eliminate them.