Update nokogiri
This fixes the following security issue:
Name: nokogiri
Version: 1.10.5
Advisory: CVE-2020-7595
Criticality: Medium
URL: https://github.com/sparklemotion/nokogiri/issues/1992
Title: libxml2 2.9.10 has an infinite loop in a certain end-of-file situation
Solution: upgrade to >= 1.10.8