Bump nokogiri from 1.10.4 to 1.10.8 in /fixture_rails_root

Bumps [nokogiri](https://github.com/sparklemotion/nokogiri) from 1.10.4 to 1.10.8.
- [Release notes](https://github.com/sparklemotion/nokogiri/releases)
- [Changelog](https://github.com/sparklemotion/nokogiri/blob/master/CHANGELOG.md)
- [Commits](sparklemotion/nokogiri@v1.10.4...v1.10.8)

Signed-off-by: dependabot[bot] <support@github.com>

fixture_rails_root/Gemfile.lock

@@ -111,7 +111,7 @@ GEM
     mini_portile2 (2.4.0)
     minitest (5.13.0)
     nio4r (2.5.2)
-    nokogiri (1.10.4)
+    nokogiri (1.10.8)
       mini_portile2 (~> 2.4.0)
     public_suffix (4.0.1)
     puma (3.12.1)