problem with Springer scraper

[Robert Jäschke]

Could not scrape the URL https://link.springer.com/article/10.1007/s11192-014-1292-9/fulltext.html. Message was: java.io.IOException: http://citation-needed.services.springer.com/v2/references/10.1007/s11192-014-1292-9/fulltext.html?format=bibtex&flavour=citation returns: 40

[Robert Jäschke]

fixes #2780 and cleans up test data

→ <<cset 6bda8ecf6c3f>>