Use latest RDoc release instead of Ruby 3.2's default version

st0012 · st0012 · commit 36b8a0d1df2c · 2025-05-19T21:30:07.000+01:00
diff --git a/Gemfile b/Gemfile
@@ -6,4 +6,5 @@ group :development do
   gem "test-unit"
   gem "coveralls"
   gem "rubocop"
+  gem "rdoc"
 end
