Update gem lockfile to allow installing with Ruby 3.0 or later (#237)

The `ruby_dep` indirect dependency prevented running `bundle install`
when using Ruby 3.0 or later.

Gemfile.lock

@@ -1,47 +1,47 @@
 GEM
   remote: https://rubygems.org/
   specs:
-    addressable (2.7.0)
+    addressable (2.8.0)
       public_suffix (>= 2.0.2, < 5.0)
     colorator (1.1.0)
-    concurrent-ruby (1.1.5)
+    concurrent-ruby (1.1.9)
-    em-websocket (0.5.1)
+    em-websocket (0.5.2)
       eventmachine (>= 0.12.9)
       http_parser.rb (~> 0.6.0)
-    ethon (0.12.0)
+    ethon (0.14.0)
-      ffi (>= 1.3.0)
+      ffi (>= 1.15.0)
     eventmachine (1.2.7)
-    ffi (1.11.1)
+    ffi (1.15.3)
     forwardable-extended (2.6.0)
-    html-proofer (3.12.2)
+    html-proofer (3.19.2)
       addressable (~> 2.3)
       mercenary (~> 0.3)
-      nokogiri (~> 1.10)
+      nokogumbo (~> 2.0)
       parallel (~> 1.3)
       rainbow (~> 3.0)
       typhoeus (~> 1.3)
       yell (~> 2.0)
     http_parser.rb (0.6.0)
-    i18n (1.6.0)
+    i18n (1.8.10)
       concurrent-ruby (~> 1.0)
-    jekyll (4.0.0)
+    jekyll (4.2.0)
       addressable (~> 2.4)
       colorator (~> 1.0)
       em-websocket (~> 0.5)
-      i18n (>= 0.9.5, < 2)
+      i18n (~> 1.0)
       jekyll-sass-converter (~> 2.0)
       jekyll-watch (~> 2.0)
-      kramdown (~> 2.1)
+      kramdown (~> 2.3)
       kramdown-parser-gfm (~> 1.0)
       liquid (~> 4.0)
-      mercenary (~> 0.3.3)
+      mercenary (~> 0.4.0)
       pathutil (~> 0.9)
       rouge (~> 3.0)
       safe_yaml (~> 1.0)
-      terminal-table (~> 1.8)
+      terminal-table (~> 2.0)
-    jekyll-redirect-from (0.15.0)
+    jekyll-redirect-from (0.16.0)
       jekyll (>= 3.3, < 5.0)
-    jekyll-sass-converter (2.0.0)
+    jekyll-sass-converter (2.1.0)
       sassc (> 2.0.1, < 3.0)
     jekyll-watch (2.2.1)
       listen (~> 3.0)
@@ -50,39 +50,37 @@ GEM
     kramdown-parser-gfm (1.1.0)
       kramdown (~> 2.0)
     liquid (4.0.3)
-    listen (3.1.5)
+    listen (3.7.0)
-      rb-fsevent (~> 0.9, >= 0.9.4)
+      rb-fsevent (~> 0.10, >= 0.10.3)
-      rb-inotify (~> 0.9, >= 0.9.7)
+      rb-inotify (~> 0.9, >= 0.9.10)
-      ruby_dep (~> 1.2)
+    mercenary (0.4.0)
-    mercenary (0.3.6)
+    nokogiri (1.12.4-x86_64-linux)
-    mini_portile2 (2.5.1)
-    nokogiri (1.11.5)
-      mini_portile2 (~> 2.5.0)
       racc (~> 1.4)
-    parallel (1.17.0)
+    nokogumbo (2.0.5)
+      nokogiri (~> 1.8, >= 1.8.4)
+    parallel (1.20.1)
     pathutil (0.16.2)
       forwardable-extended (~> 2.6)
-    public_suffix (4.0.1)
+    public_suffix (4.0.6)
     racc (1.5.2)
     rainbow (3.0.0)
-    rb-fsevent (0.10.3)
+    rb-fsevent (0.11.0)
-    rb-inotify (0.10.0)
+    rb-inotify (0.10.1)
       ffi (~> 1.0)
     rexml (3.2.5)
-    rouge (3.10.0)
+    rouge (3.26.0)
-    ruby_dep (1.5.0)
     safe_yaml (1.0.5)
-    sassc (2.2.0)
+    sassc (2.4.0)
       ffi (~> 1.9)
-    terminal-table (1.8.0)
+    terminal-table (2.0.0)
       unicode-display_width (~> 1.1, >= 1.1.1)
-    typhoeus (1.3.1)
+    typhoeus (1.4.0)
       ethon (>= 0.9.0)
-    unicode-display_width (1.6.0)
+    unicode-display_width (1.7.0)
-    yell (2.2.0)
+    yell (2.2.2)
 
 PLATFORMS
-  ruby
+  x86_64-linux
 
 DEPENDENCIES
   html-proofer
@@ -91,4 +89,4 @@ DEPENDENCIES
   tzinfo-data
 
 BUNDLED WITH
-   2.0.2
+   2.2.26