Bump nokogiri from 1.10.3 to 1.10.4 (#407)

Bumps [nokogiri](https://github.com/sparklemotion/nokogiri) from 1.10.3 to 1.10.4.
- [Release notes](https://github.com/sparklemotion/nokogiri/releases)
- [Changelog](https://github.com/sparklemotion/nokogiri/blob/master/CHANGELOG.md)
- [Commits](sparklemotion/nokogiri@v1.10.3...v1.10.4)

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

Author: dependabot[bot]

Gemfile.lock

@@ -8,7 +8,7 @@ GEM
     method_source (0.9.0)
     mini_portile2 (2.4.0)
     multipart-post (2.1.1)
-    nokogiri (1.10.3)
+    nokogiri (1.10.4)
       mini_portile2 (~> 2.4.0)
     pry (0.11.3)
       coderay (~> 1.1.0)