Update to Ruby 3.2.0

Required minor changes since File.exists? is now File.exist?

.ruby-version

@@ -1 +1 @@
-3.1.2
+3.2.0

config.rb

@@ -197,9 +197,9 @@ helpers do
     language_name = language.last[:name]
     language_path = "source/#{language.first}"
 
-    if File.exists?("#{language_path}/#{$last_version}")
+    if File.exist?("#{language_path}/#{$last_version}")
       "#{$last_version} #{language_name}"
-    elsif File.exists?("#{language_path}/#{$previous_version}")
+    elsif File.exist?("#{language_path}/#{$previous_version}")
       "#{$previous_version} #{language_name}"
     else
       nil

source/layouts/layout.html.haml

@@ -4,7 +4,7 @@
 - language_code = current_page.metadata[:page][:language]
 - versions = Dir.entries("source/#{language_code}") - %w[. ..]
 - current_version = current_page.metadata[:page][:version]
-- newer_version_available = File.exists?("source/#{language_code}/#{$last_version}")
+- newer_version_available = File.exist?("source/#{language_code}/#{$last_version}")
 
 !!! 5
 %html