Update bundler

Gemfile.lock

@@ -45,8 +45,8 @@ GEM
       jekyll (>= 3.7, < 5.0)
     jekyll-watch (2.2.1)
       listen (~> 3.0)
-    kramdown (2.4.0)
-      rexml
+    kramdown (2.5.1)
+      rexml (>= 3.3.9)
     kramdown-parser-gfm (1.1.0)
       kramdown (~> 2.0)
     liquid (4.0.4)
@@ -63,9 +63,9 @@ GEM
       ffi (~> 1.0)
     rexml (3.3.9)
     rmagick (4.3.0)
-    rouge (4.4.0)
+    rouge (4.5.1)
     safe_yaml (1.0.5)
-    sass-embedded (1.80.6-x86_64-linux-gnu)
+    sass-embedded (1.81.0-x86_64-linux-gnu)
       google-protobuf (~> 4.28)
     terminal-table (3.0.2)
       unicode-display_width (>= 1.1.1, < 3)
@@ -84,4 +84,4 @@ DEPENDENCIES
   tzinfo-data
 
 BUNDLED WITH
-   2.4.13
+   2.5.23

bin/upgrade

@@ -5,5 +5,6 @@ nix-shell -p ruby_3_3 imagemagick pkg-config --pure --command "
   echo 'Installing bundles'
   bundle config set path 'vendor/cache'
   bundle install --gemfile=Gemfile
+  bundle update --bundler
   bundle update
 "