No, the package is libxml2 and the repository is core (this has nothing to do with the coreutils package).
wkhtmltopdf is up to date (version 0.12.6-3)? If yes, then this is because libxml2 has been updated and provides a new version of libxml2.so.x - wkhtmltopdf requires the previous version of libxml2. I advise you not to downgrade libxml2, too many packages depend on it. Just wait until an updated version of wkhtmltopdf is available.