Bump nokogiri from 1.10.9 to 1.13.9

Gemfile.lock

@@ -4,20 +4,20 @@ GEM
     addressable (2.7.0)
       public_suffix (>= 2.0.2, < 5.0)
     colorator (1.1.0)
-    concurrent-ruby (1.1.6)
+    concurrent-ruby (1.1.10)
     em-websocket (0.5.1)
       eventmachine (>= 0.12.9)
       http_parser.rb (~> 0.6.0)
     eventmachine (1.2.7)
     execjs (2.7.0)
-    faraday (0.17.3)
+    faraday (0.17.5)
       multipart-post (>= 1.2, < 3)
     ffi (1.12.2)
     forwardable-extended (2.6.0)
     http_parser.rb (0.6.0)
-    i18n (1.8.2)
+    i18n (1.12.0)
       concurrent-ruby (~> 1.0)
-    jekyll (4.0.0)
+    jekyll (4.0.1)
       addressable (~> 2.4)
       colorator (~> 1.0)
       em-websocket (~> 0.5)
@@ -32,7 +32,7 @@ GEM
       rouge (~> 3.0)
       safe_yaml (~> 1.0)
       terminal-table (~> 1.8)
-    jekyll-feed (0.13.0)
+    jekyll-feed (0.17.0)
       jekyll (>= 3.7, < 5.0)
     jekyll-gist (1.5.0)
       octokit (~> 4.2)
@@ -57,7 +57,7 @@ GEM
     jekyll-twitter-plugin (2.1.0)
     jekyll-watch (2.2.1)
       listen (~> 3.0)
-    katex (0.6.0)
+    katex (0.9.0)
       execjs (~> 2.7)
     kramdown (2.1.0)
     kramdown-math-katex (1.0.1)
@@ -66,18 +66,19 @@ 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)
     multipart-post (2.1.1)
-    nokogiri (1.10.9)
-      mini_portile2 (~> 2.4.0)
+    nokogiri (1.13.9)
+      mini_portile2 (~> 2.8.0)
+      racc (~> 1.4)
     octicons (9.5.0)
       nokogiri (>= 1.6.3.1)
     octokit (4.16.0)
@@ -86,6 +87,7 @@ GEM
     pathutil (0.16.2)
       forwardable-extended (~> 2.6)
     public_suffix (4.0.3)
+    racc (1.6.0)
     rb-fsevent (0.10.3)
     rb-inotify (0.10.1)
       ffi (~> 1.0)
@@ -100,7 +102,7 @@ GEM
     terminal-table (1.8.0)
       unicode-display_width (~> 1.1, >= 1.1.1)
     thread_safe (0.3.6)
-    tzinfo (1.2.6)
+    tzinfo (1.2.10)
       thread_safe (~> 0.1)
     tzinfo-data (1.2019.3)
       tzinfo (>= 1.0.0)