Bump github-pages from 215 to 221 in /docs

Bumps [github-pages](https://github.com/github/pages-gem) from 215 to 221.
- [Release notes](https://github.com/github/pages-gem/releases)
- [Commits](github/pages-gem@v215...v221)

---
updated-dependencies:
- dependency-name: github-pages
  dependency-type: direct:development
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

docs/Gemfile.lock

@@ -1,7 +1,7 @@
 GEM
   remote: https://rubygems.org/
   specs:
-    activesupport (6.0.4)
+    activesupport (6.0.4.1)
       concurrent-ruby (~> 1.0, >= 1.0.2)
       i18n (>= 0.7, < 2)
       minitest (~> 5.1)
@@ -22,18 +22,19 @@ GEM
     em-websocket (0.5.2)
       eventmachine (>= 0.12.9)
       http_parser.rb (~> 0.6.0)
-    ethon (0.14.0)
+    ethon (0.15.0)
       ffi (>= 1.15.0)
     eventmachine (1.2.7)
     execjs (2.8.1)
-    faraday (1.5.1)
+    faraday (1.8.0)
       faraday-em_http (~> 1.0)
       faraday-em_synchrony (~> 1.0)
       faraday-excon (~> 1.1)
       faraday-httpclient (~> 1.0.1)
       faraday-net_http (~> 1.0)
       faraday-net_http_persistent (~> 1.1)
       faraday-patron (~> 1.0)
+      faraday-rack (~> 1.0)
       multipart-post (>= 1.2, < 3)
       ruby2_keywords (>= 0.0.4)
     faraday-em_http (1.0.0)
@@ -43,11 +44,12 @@ GEM
     faraday-net_http (1.0.1)
     faraday-net_http_persistent (1.2.0)
     faraday-patron (1.0.0)
-    ffi (1.15.3)
+    faraday-rack (1.0.0)
+    ffi (1.15.4)
     forwardable-extended (2.6.0)
     gemoji (3.0.1)
-    github-pages (215)
-      github-pages-health-check (= 1.17.2)
+    github-pages (221)
+      github-pages-health-check (= 1.17.9)
       jekyll (= 3.9.0)
       jekyll-avatar (= 0.7.0)
       jekyll-coffeescript (= 1.1.1)
@@ -67,34 +69,34 @@ GEM
       jekyll-seo-tag (= 2.7.1)
       jekyll-sitemap (= 1.4.0)
       jekyll-swiss (= 1.0.0)
-      jekyll-theme-architect (= 0.1.1)
-      jekyll-theme-cayman (= 0.1.1)
-      jekyll-theme-dinky (= 0.1.1)
-      jekyll-theme-hacker (= 0.1.2)
-      jekyll-theme-leap-day (= 0.1.1)
-      jekyll-theme-merlot (= 0.1.1)
-      jekyll-theme-midnight (= 0.1.1)
-      jekyll-theme-minimal (= 0.1.1)
-      jekyll-theme-modernist (= 0.1.1)
-      jekyll-theme-primer (= 0.5.4)
-      jekyll-theme-slate (= 0.1.1)
-      jekyll-theme-tactile (= 0.1.1)
-      jekyll-theme-time-machine (= 0.1.1)
+      jekyll-theme-architect (= 0.2.0)
+      jekyll-theme-cayman (= 0.2.0)
+      jekyll-theme-dinky (= 0.2.0)
+      jekyll-theme-hacker (= 0.2.0)
+      jekyll-theme-leap-day (= 0.2.0)
+      jekyll-theme-merlot (= 0.2.0)
+      jekyll-theme-midnight (= 0.2.0)
+      jekyll-theme-minimal (= 0.2.0)
+      jekyll-theme-modernist (= 0.2.0)
+      jekyll-theme-primer (= 0.6.0)
+      jekyll-theme-slate (= 0.2.0)
+      jekyll-theme-tactile (= 0.2.0)
+      jekyll-theme-time-machine (= 0.2.0)
       jekyll-titles-from-headings (= 0.5.3)
       jemoji (= 0.12.0)
       kramdown (= 2.3.1)
       kramdown-parser-gfm (= 1.1.0)
       liquid (= 4.0.3)
       mercenary (~> 0.3)
       minima (= 2.5.1)
-      nokogiri (>= 1.10.4, < 2.0)
+      nokogiri (>= 1.12.5, < 2.0)
       rouge (= 3.26.0)
       terminal-table (~> 1.4)
-    github-pages-health-check (1.17.2)
+    github-pages-health-check (1.17.9)
       addressable (~> 2.3)
       dnsruby (~> 1.60)
       octokit (~> 4.0)
-      public_suffix (>= 2.0.2, < 5.0)
+      public_suffix (>= 3.0, < 5.0)
       typhoeus (~> 1.3)
     html-pipeline (2.14.0)
       activesupport (>= 2)
@@ -160,45 +162,45 @@ GEM
     jekyll-sitemap (1.4.0)
       jekyll (>= 3.7, < 5.0)
     jekyll-swiss (1.0.0)
-    jekyll-theme-architect (0.1.1)
-      jekyll (~> 3.5)
+    jekyll-theme-architect (0.2.0)
+      jekyll (> 3.5, < 5.0)
       jekyll-seo-tag (~> 2.0)
-    jekyll-theme-cayman (0.1.1)
-      jekyll (~> 3.5)
+    jekyll-theme-cayman (0.2.0)
+      jekyll (> 3.5, < 5.0)
       jekyll-seo-tag (~> 2.0)
-    jekyll-theme-dinky (0.1.1)
-      jekyll (~> 3.5)
+    jekyll-theme-dinky (0.2.0)
+      jekyll (> 3.5, < 5.0)
       jekyll-seo-tag (~> 2.0)
-    jekyll-theme-hacker (0.1.2)
+    jekyll-theme-hacker (0.2.0)
       jekyll (> 3.5, < 5.0)
       jekyll-seo-tag (~> 2.0)
-    jekyll-theme-leap-day (0.1.1)
-      jekyll (~> 3.5)
+    jekyll-theme-leap-day (0.2.0)
+      jekyll (> 3.5, < 5.0)
       jekyll-seo-tag (~> 2.0)
-    jekyll-theme-merlot (0.1.1)
-      jekyll (~> 3.5)
+    jekyll-theme-merlot (0.2.0)
+      jekyll (> 3.5, < 5.0)
       jekyll-seo-tag (~> 2.0)
-    jekyll-theme-midnight (0.1.1)
-      jekyll (~> 3.5)
+    jekyll-theme-midnight (0.2.0)
+      jekyll (> 3.5, < 5.0)
       jekyll-seo-tag (~> 2.0)
-    jekyll-theme-minimal (0.1.1)
-      jekyll (~> 3.5)
+    jekyll-theme-minimal (0.2.0)
+      jekyll (> 3.5, < 5.0)
       jekyll-seo-tag (~> 2.0)
-    jekyll-theme-modernist (0.1.1)
-      jekyll (~> 3.5)
+    jekyll-theme-modernist (0.2.0)
+      jekyll (> 3.5, < 5.0)
       jekyll-seo-tag (~> 2.0)
-    jekyll-theme-primer (0.5.4)
+    jekyll-theme-primer (0.6.0)
       jekyll (> 3.5, < 5.0)
       jekyll-github-metadata (~> 2.9)
       jekyll-seo-tag (~> 2.0)
-    jekyll-theme-slate (0.1.1)
-      jekyll (~> 3.5)
+    jekyll-theme-slate (0.2.0)
+      jekyll (> 3.5, < 5.0)
       jekyll-seo-tag (~> 2.0)
-    jekyll-theme-tactile (0.1.1)
-      jekyll (~> 3.5)
+    jekyll-theme-tactile (0.2.0)
+      jekyll (> 3.5, < 5.0)
       jekyll-seo-tag (~> 2.0)
-    jekyll-theme-time-machine (0.1.1)
-      jekyll (~> 3.5)
+    jekyll-theme-time-machine (0.2.0)
+      jekyll (> 3.5, < 5.0)
       jekyll-seo-tag (~> 2.0)
     jekyll-titles-from-headings (0.5.3)
       jekyll (>= 3.3, < 5.0)
@@ -214,19 +216,19 @@ GEM
       kramdown (~> 2.0)
     libv8 (3.16.14.19)
     liquid (4.0.3)
-    listen (3.5.1)
+    listen (3.7.0)
       rb-fsevent (~> 0.10, >= 0.10.3)
       rb-inotify (~> 0.9, >= 0.9.10)
     mercenary (0.3.6)
-    mini_portile2 (2.5.3)
+    mini_portile2 (2.6.1)
     minima (2.5.1)
       jekyll (>= 3.5, < 5.0)
       jekyll-feed (~> 0.9)
       jekyll-seo-tag (~> 2.1)
     minitest (5.14.4)
     multipart-post (2.1.1)
-    nokogiri (1.11.7)
-      mini_portile2 (~> 2.5.0)
+    nokogiri (1.12.5)
+      mini_portile2 (~> 2.6.1)
       racc (~> 1.4)
     octokit (4.21.0)
       faraday (>= 0.9)
@@ -268,8 +270,8 @@ GEM
       thread_safe (~> 0.1)
     unf (0.1.4)
       unf_ext
-    unf_ext (0.0.7.7)
-    unicode-display_width (1.7.0)
+    unf_ext (0.0.8)
+    unicode-display_width (1.8.0)
     zeitwerk (2.4.2)
 
 PLATFORMS