Bump nokogiri from 1.10.8 to 1.13.9 in /docs

Bumps [nokogiri](https://github.com/sparklemotion/nokogiri) from 1.10.8 to 1.13.9.
- [Release notes](https://github.com/sparklemotion/nokogiri/releases)
- [Changelog](https://github.com/sparklemotion/nokogiri/blob/main/CHANGELOG.md)
- [Commits](sparklemotion/nokogiri@v1.10.8...v1.13.9)

---
updated-dependencies:
- dependency-name: nokogiri
  dependency-type: direct:production
...

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

Author: dependabot[bot]

docs/Gemfile

@@ -3,6 +3,6 @@ source "https://rubygems.org"
 gem 'github-pages', group: :jekyll_plugins
 
 # Added at 2019-11-25 10:11:40 -0800 by jhoward:
-gem "nokogiri", "< 1.10.9"
+gem "nokogiri", "< 1.13.10"
 gem "jekyll", ">= 3.7"
 gem "kramdown", ">= 2.3.0"

docs/Gemfile.lock

@@ -1,7 +1,7 @@
 GEM
   remote: https://rubygems.org/
   specs:
-    activesupport (6.0.3.2)
+    activesupport (6.0.6)
       concurrent-ruby (~> 1.0, >= 1.0.2)
       i18n (>= 0.7, < 2)
       minitest (~> 5.1)
@@ -81,7 +81,7 @@ GEM
       octokit (~> 4.0)
       public_suffix (~> 3.0)
       typhoeus (~> 1.3)
-    html-pipeline (2.14.0)
+    html-pipeline (2.14.3)
       activesupport (>= 2)
       nokogiri (>= 1.4)
     http_parser.rb (0.6.0)
@@ -197,33 +197,35 @@ GEM
     kramdown-parser-gfm (1.1.0)
       kramdown (~> 2.0)
     liquid (4.0.3)
-    listen (3.2.1)
+    listen (3.7.1)
       rb-fsevent (~> 0.10, >= 0.10.3)
       rb-inotify (~> 0.9, >= 0.9.10)
     mercenary (0.3.6)
-    mini_portile2 (2.4.0)
+    mini_portile2 (2.8.0)
     minima (2.5.1)
       jekyll (>= 3.5, < 5.0)
       jekyll-feed (~> 0.9)
       jekyll-seo-tag (~> 2.1)
-    minitest (5.14.1)
+    minitest (5.16.3)
     multipart-post (2.1.1)
-    nokogiri (1.10.8)
-      mini_portile2 (~> 2.4.0)
+    nokogiri (1.13.9)
+      mini_portile2 (~> 2.8.0)
+      racc (~> 1.4)
     octokit (4.18.0)
       faraday (>= 0.9)
       sawyer (~> 0.8.0, >= 0.5.3)
     pathutil (0.16.2)
       forwardable-extended (~> 2.6)
     public_suffix (3.1.1)
+    racc (1.6.0)
     rb-fsevent (0.10.4)
     rb-inotify (0.10.1)
       ffi (~> 1.0)
     rexml (3.2.4)
     rouge (3.19.0)
     ruby-enum (0.8.0)
       i18n
-    rubyzip (2.3.0)
+    rubyzip (2.3.2)
     safe_yaml (1.0.5)
     sass (3.7.4)
       sass-listen (~> 4.0.0)
@@ -246,7 +248,7 @@ GEM
       unf_ext
     unf_ext (0.0.7.7)
     unicode-display_width (1.7.0)
-    zeitwerk (2.4.0)
+    zeitwerk (2.6.1)
 
 PLATFORMS
   ruby
@@ -255,7 +257,7 @@ DEPENDENCIES
   github-pages
   jekyll (>= 3.7)
   kramdown (>= 2.3.0)
-  nokogiri (< 1.10.9)
+  nokogiri (< 1.13.10)
 
 BUNDLED WITH
    2.0.2