[Security] Bump nokogiri from 1.10.2 to 1.10.3

Bumps [nokogiri](https://github.com/sparklemotion/nokogiri) from 1.10.2 to 1.10.3. **This update includes security fixes.**
- [Release notes](https://github.com/sparklemotion/nokogiri/releases)
- [Changelog](https://github.com/sparklemotion/nokogiri/blob/master/CHANGELOG.md)
- [Commits](sparklemotion/nokogiri@v1.10.2...v1.10.3)

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

Gemfile.lock

@@ -51,7 +51,7 @@ GEM
     mini_mime (1.0.1)
     mini_portile2 (2.4.0)
     multipart-post (2.0.0)
-    nokogiri (1.10.2)
+    nokogiri (1.10.3)
       mini_portile2 (~> 2.4.0)
     octokit (4.14.0)
       sawyer (~> 0.8.0, >= 0.5.3)