Bump nokogiri from 1.10.5 to 1.10.9

Bumps [nokogiri](https://github.com/sparklemotion/nokogiri) from 1.10.5 to 1.10.9.
- [Release notes](https://github.com/sparklemotion/nokogiri/releases)
- [Changelog](https://github.com/sparklemotion/nokogiri/blob/v1.10.9/CHANGELOG.md)
- [Commits](sparklemotion/nokogiri@v1.10.5...v1.10.9)

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

Author: dependabot[bot]

Gemfile.lock

@@ -233,11 +233,11 @@ GEM
       jekyll-seo-tag (~> 2.1)
     minitest (5.11.3)
     multipart-post (2.0.0)
-    nokogiri (1.10.5)
+    nokogiri (1.10.9)
       mini_portile2 (~> 2.4.0)
-    nokogiri (1.10.5-x64-mingw32)
+    nokogiri (1.10.9-x64-mingw32)
       mini_portile2 (~> 2.4.0)
-    nokogiri (1.10.5-x86-mingw32)
+    nokogiri (1.10.9-x86-mingw32)
       mini_portile2 (~> 2.4.0)
     octokit (4.12.0)
       sawyer (~> 0.8.0, >= 0.5.3)