ceurws scraping IndexError

[fnielsen]

Describe the bug
Error in scraping a specific CEUR-WS proceedings.

To Reproduce
Steps to reproduce the behavior:

1. Go to $ python3 -m scholia.scrape.ceurws proceedings-url-to-quickstatements https://ceur-ws.org/Vol-3196
2. IndexError in lin 132

Expected behavior
quickstatements should be generated.