Bump nokogiri from 1.10.9 to 1.11.1 in /docs (#368)

Bumps [nokogiri](https://github.com/sparklemotion/nokogiri) from 1.10.9 to 1.11.1.
- [Release notes](https://github.com/sparklemotion/nokogiri/releases)
- [Changelog](https://github.com/sparklemotion/nokogiri/blob/master/CHANGELOG.md)
- [Commits](https://github.com/sparklemotion/nokogiri/compare/v1.10.9...v1.11.1)

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

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

docs/Gemfile.lock

@@ -200,22 +200,24 @@ GEM
       rb-inotify (~> 0.9, >= 0.9.7)
       ruby_dep (~> 1.2)
     mercenary (0.3.6)
-    mini_portile2 (2.4.0)
+    mini_portile2 (2.5.0)
     minima (2.5.0)
       jekyll (~> 3.5)
       jekyll-feed (~> 0.9)
       jekyll-seo-tag (~> 2.1)
     minitest (5.11.3)
     multipart-post (2.0.0)
-    nokogiri (1.10.9)
-      mini_portile2 (~> 2.4.0)
-    nokogiri (1.10.9-x64-mingw32)
-      mini_portile2 (~> 2.4.0)
+    nokogiri (1.11.1)
+      mini_portile2 (~> 2.5.0)
+      racc (~> 1.4)
+    nokogiri (1.11.1-x64-mingw32)
+      racc (~> 1.4)
     octokit (4.13.0)
       sawyer (~> 0.8.0, >= 0.5.3)
     pathutil (0.16.2)
       forwardable-extended (~> 2.6)
     public_suffix (3.0.3)
+    racc (1.5.2)
     rb-fsevent (0.10.3)
     rb-inotify (0.10.0)
       ffi (~> 1.0)