fix: Gemfile & Gemfile.lock to reduce vulnerabilities

The following vulnerabilities are fixed with an upgrade:
- https://snyk.io/vuln/SNYK-RUBY-NOKOGIRI-9789079

Author: snyk-bot

Gemfile

@@ -15,7 +15,7 @@ gem "minima"
 # If you have any plugins, put them here!
 group :jekyll_plugins do
   gem "jekyll-feed", "~> 0.12"
-  gem 'jekyll-octicons'
+  gem 'jekyll-octicons', '>= 14.2.0'
   gem 'jekyll-remote-theme'
   gem "jekyll-twitter-plugin"
   gem 'jekyll-relative-links'

Gemfile.lock

@@ -7,25 +7,25 @@ GEM
       minitest (~> 5.1)
       tzinfo (~> 1.1)
       zeitwerk (~> 2.2, >= 2.2.2)
-    addressable (2.8.0)
-      public_suffix (>= 2.0.2, < 5.0)
+    addressable (2.8.7)
+      public_suffix (>= 2.0.2, < 7.0)
     colorator (1.1.0)
-    concurrent-ruby (1.1.7)
-    em-websocket (0.5.1)
+    concurrent-ruby (1.3.5)
+    em-websocket (0.5.3)
       eventmachine (>= 0.12.9)
-      http_parser.rb (~> 0.6.0)
+      http_parser.rb (~> 0)
     eventmachine (1.2.7)
     execjs (2.7.0)
     faraday (0.17.3)
       multipart-post (>= 1.2, < 3)
-    ffi (1.13.1)
+    ffi (1.17.2)
     forwardable-extended (2.6.0)
     gemoji (3.0.1)
     html-pipeline (2.14.0)
       activesupport (>= 2)
       nokogiri (>= 1.4)
-    http_parser.rb (0.6.0)
-    i18n (1.8.5)
+    http_parser.rb (0.8.0)
+    i18n (1.14.7)
       concurrent-ruby (~> 1.0)
     jekyll (4.1.1)
       addressable (~> 2.4)
@@ -46,9 +46,9 @@ GEM
       jekyll (>= 3.7, < 5.0)
     jekyll-gist (1.5.0)
       octokit (~> 4.2)
-    jekyll-octicons (11.0.0)
+    jekyll-octicons (19.8.0)
       jekyll (>= 3.6, < 5.0)
-      octicons (= 11.0.0)
+      octicons (= 19.8.0)
     jekyll-paginate (1.1.0)
     jekyll-relative-links (0.6.1)
       jekyll (>= 3.3, < 5.0)
@@ -57,7 +57,7 @@ GEM
       jekyll (>= 3.5, < 5.0)
       jekyll-sass-converter (>= 1.0, <= 3.0.0, != 2.0.0)
       rubyzip (>= 1.3.0, < 3.0)
-    jekyll-sass-converter (2.1.0)
+    jekyll-sass-converter (2.2.0)
       sassc (> 2.0.1, < 3.0)
     jekyll-seo-tag (2.6.1)
       jekyll (>= 3.3, < 5.0)
@@ -75,15 +75,15 @@ GEM
       jekyll (>= 3.0, < 5.0)
     katex (0.6.0)
       execjs (~> 2.7)
-    kramdown (2.3.1)
-      rexml
+    kramdown (2.5.1)
+      rexml (>= 3.3.9)
     kramdown-math-katex (1.0.1)
       katex (~> 0.4)
       kramdown (~> 2.0)
     kramdown-parser-gfm (1.1.0)
       kramdown (~> 2.0)
-    liquid (4.0.3)
-    listen (3.2.1)
+    liquid (4.0.4)
+    listen (3.9.0)
       rb-fsevent (~> 0.10, >= 0.10.3)
       rb-inotify (~> 0.9, >= 0.9.10)
     mercenary (0.4.0)
@@ -94,23 +94,22 @@ GEM
       jekyll-seo-tag (~> 2.1)
     minitest (5.14.2)
     multipart-post (2.1.1)
-    nokogiri (1.18.3)
+    nokogiri (1.15.7)
       mini_portile2 (~> 2.8.2)
       racc (~> 1.4)
-    octicons (11.0.0)
-      nokogiri (>= 1.6.3.1)
+    octicons (19.8.0)
     octokit (4.18.0)
       faraday (>= 0.9)
       sawyer (~> 0.8.0, >= 0.5.3)
     pathutil (0.16.2)
       forwardable-extended (~> 2.6)
-    public_suffix (4.0.6)
+    public_suffix (5.1.1)
     racc (1.8.1)
-    rb-fsevent (0.10.4)
-    rb-inotify (0.10.1)
+    rb-fsevent (0.11.2)
+    rb-inotify (0.11.1)
       ffi (~> 1.0)
-    rexml (3.3.9)
-    rouge (3.23.0)
+    rexml (3.4.1)
+    rouge (3.30.0)
     rubyzip (2.3.0)
     safe_yaml (1.0.5)
     sassc (2.4.0)
@@ -125,7 +124,7 @@ GEM
       thread_safe (~> 0.1)
     tzinfo-data (1.2020.1)
       tzinfo (>= 1.0.0)
-    unicode-display_width (1.7.0)
+    unicode-display_width (1.8.0)
     wdm (0.1.1)
     zeitwerk (2.4.0)
 
@@ -137,7 +136,7 @@ DEPENDENCIES
   jekyll (~> 4.1.0)
   jekyll-feed (~> 0.12)
   jekyll-gist
-  jekyll-octicons
+  jekyll-octicons (>= 14.2.0)
   jekyll-paginate
   jekyll-relative-links
   jekyll-remote-theme