Bump github-pages from 185 to 186 in /docs

Bumps [github-pages](https://github.com/github/pages-gem) from 185 to 186.
- [Release notes](https://github.com/github/pages-gem/releases)
- [Commits](https://github.com/github/pages-gem/compare/v185...v186)

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

docs/Gemfile.lock

@@ -1,7 +1,7 @@
 GEM
   remote: https://rubygems.org/
   specs:
-    activesupport (4.2.9)
+    activesupport (4.2.10)
       i18n (~> 0.7)
       minitest (~> 5.1)
       thread_safe (~> 0.3, >= 0.3.4)
@@ -24,13 +24,13 @@ GEM
       ffi (>= 1.3.0)
     eventmachine (1.2.7)
     execjs (2.7.0)
-    faraday (0.15.1)
+    faraday (0.15.2)
       multipart-post (>= 1.2, < 3)
     ffi (1.9.23)
     forwardable-extended (2.6.0)
     gemoji (3.0.0)
-    github-pages (185)
+    github-pages (186)
-      activesupport (= 4.2.9)
+      activesupport (= 4.2.10)
       github-pages-health-check (= 1.8.1)
       jekyll (= 3.7.3)
       jekyll-avatar (= 0.5.0)
@@ -71,7 +71,7 @@ GEM
       listen (= 3.1.5)
       mercenary (~> 0.3)
       minima (= 2.4.1)
-      nokogiri (>= 1.8.1, < 2.0)
+      nokogiri (>= 1.8.2, < 2.0)
       rouge (= 2.2.1)
       terminal-table (~> 1.4)
     github-pages-health-check (1.8.1)
@@ -237,7 +237,7 @@ GEM
       ethon (>= 0.9.0)
     tzinfo (1.2.5)
       thread_safe (~> 0.1)
-    unicode-display_width (1.3.2)
+    unicode-display_width (1.3.3)
 
 PLATFORMS
   ruby