Bump html-proofer from 3.15.3 to 3.16.0 (#210)

Bumps [html-proofer](https://github.com/gjtorikian/html-proofer) from 3.15.3 to 3.16.0.
- [Release notes](https://github.com/gjtorikian/html-proofer/releases)
- [Commits](gjtorikian/html-proofer@v3.15.3...v3.16.0)

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

Co-authored-by: dependabot-preview[bot] <27856297+dependabot-preview[bot]@users.noreply.github.com>

Gemfile.lock

@@ -15,7 +15,7 @@ GEM
       multipart-post (>= 1.2, < 3)
     ffi (1.13.1)
     forwardable-extended (2.6.0)
-    html-proofer (3.15.3)
+    html-proofer (3.16.0)
       addressable (~> 2.3)
       mercenary (~> 0.3)
       nokogumbo (~> 2.0)
@@ -61,13 +61,13 @@ GEM
     mercenary (0.4.0)
     mini_portile2 (2.4.0)
     multipart-post (2.0.0)
-    nokogiri (1.10.9)
+    nokogiri (1.10.10)
       mini_portile2 (~> 2.4.0)
     nokogumbo (2.0.2)
       nokogiri (~> 1.8, >= 1.8.4)
     octokit (4.13.0)
       sawyer (~> 0.8.0, >= 0.5.3)
-    parallel (1.19.1)
+    parallel (1.19.2)
     pathutil (0.16.2)
       forwardable-extended (~> 2.6)
     public_suffix (3.1.1)
@@ -85,7 +85,7 @@ GEM
       faraday (~> 0.8, < 1.0)
     terminal-table (1.8.0)
       unicode-display_width (~> 1.1, >= 1.1.1)
-    typhoeus (1.3.1)
+    typhoeus (1.4.0)
       ethon (>= 0.9.0)
     unicode-display_width (1.7.0)
     yell (2.2.2)