Update GitHub Actions to Ruby 3

A long time ago I merged #52 to upgrade to Ruby 3. I recently realized
that only actually worked locally, since I didn't touch the GitHub
Actions yml.

In this commit, I'm actually upgrading "prod" to GitHub 3 by bumping our
GitHub Actions container to 3.2.2. While I'm at it, update
`.ruby-version` to use the same thing locally, and run `bundle update`
to make sure our gems are compatible with this version.

Author: mkasberg

.github/workflows/github-pages.yml

@@ -13,7 +13,7 @@ on:
 jobs:
   github-pages:
     runs-on: ubuntu-latest
-    container: ruby:2-buster
+    container: ruby:3.2.2-bookworm
     steps:
       - uses: actions/checkout@v2
       - uses: actions/cache@v1

.ruby-version

@@ -1 +1 @@
-3.0.2
+3.2.2

Gemfile.lock

@@ -1,73 +1,77 @@
 GEM
   remote: https://rubygems.org/
   specs:
-    addressable (2.8.0)
-      public_suffix (>= 2.0.2, < 5.0)
+    addressable (2.8.5)
+      public_suffix (>= 2.0.2, < 6.0)
     colorator (1.1.0)
-    concurrent-ruby (1.1.9)
-    em-websocket (0.5.2)
+    concurrent-ruby (1.2.2)
+    em-websocket (0.5.3)
       eventmachine (>= 0.12.9)
-      http_parser.rb (~> 0.6.0)
+      http_parser.rb (~> 0)
     eventmachine (1.2.7)
-    ffi (1.15.4)
+    ffi (1.16.2)
     forwardable-extended (2.6.0)
-    http_parser.rb (0.6.0)
-    i18n (1.8.10)
+    google-protobuf (3.24.3)
+    http_parser.rb (0.8.0)
+    i18n (1.14.1)
       concurrent-ruby (~> 1.0)
-    jekyll (4.2.1)
+    jekyll (4.3.2)
       addressable (~> 2.4)
       colorator (~> 1.0)
       em-websocket (~> 0.5)
       i18n (~> 1.0)
-      jekyll-sass-converter (~> 2.0)
+      jekyll-sass-converter (>= 2.0, < 4.0)
       jekyll-watch (~> 2.0)
-      kramdown (~> 2.3)
+      kramdown (~> 2.3, >= 2.3.1)
       kramdown-parser-gfm (~> 1.0)
       liquid (~> 4.0)
-      mercenary (~> 0.4.0)
+      mercenary (>= 0.3.6, < 0.5)
       pathutil (~> 0.9)
-      rouge (~> 3.0)
+      rouge (>= 3.0, < 5.0)
       safe_yaml (~> 1.0)
-      terminal-table (~> 2.0)
+      terminal-table (>= 1.8, < 4.0)
+      webrick (~> 1.7)
     jekyll-paginate (1.1.0)
     jekyll-redirect-from (0.16.0)
       jekyll (>= 3.3, < 5.0)
-    jekyll-sass-converter (2.1.0)
-      sassc (> 2.0.1, < 3.0)
+    jekyll-sass-converter (3.0.0)
+      sass-embedded (~> 1.54)
     jekyll-watch (2.2.1)
       listen (~> 3.0)
     jekyll_html_truncatewords (0.1.2)
       liquid
       nokogiri
-    kramdown (2.3.1)
+    kramdown (2.4.0)
       rexml
     kramdown-parser-gfm (1.1.0)
       kramdown (~> 2.0)
-    liquid (4.0.3)
-    listen (3.7.0)
+    liquid (4.0.4)
+    listen (3.8.0)
       rb-fsevent (~> 0.10, >= 0.10.3)
       rb-inotify (~> 0.9, >= 0.9.10)
     mercenary (0.4.0)
-    mini_portile2 (2.8.0)
-    nokogiri (1.13.10)
-      mini_portile2 (~> 2.8.0)
+    mini_portile2 (2.8.4)
+    nokogiri (1.15.4)
+      mini_portile2 (~> 2.8.2)
       racc (~> 1.4)
     pathutil (0.16.2)
       forwardable-extended (~> 2.6)
-    public_suffix (4.0.6)
-    racc (1.6.1)
-    rb-fsevent (0.11.0)
+    public_suffix (5.0.3)
+    racc (1.7.1)
+    rake (13.0.6)
+    rb-fsevent (0.11.2)
     rb-inotify (0.10.1)
       ffi (~> 1.0)
-    rexml (3.2.5)
-    rouge (3.26.1)
+    rexml (3.2.6)
+    rouge (4.1.3)
     safe_yaml (1.0.5)
-    sassc (2.4.0)
-      ffi (~> 1.9)
-    terminal-table (2.0.0)
-      unicode-display_width (~> 1.1, >= 1.1.1)
-    unicode-display_width (1.8.0)
-    webrick (1.7.0)
+    sass-embedded (1.68.0)
+      google-protobuf (~> 3.23)
+      rake (>= 13.0.0)
+    terminal-table (3.0.2)
+      unicode-display_width (>= 1.1.1, < 3)
+    unicode-display_width (2.5.0)
+    webrick (1.8.1)
 
 PLATFORMS
   ruby