Lock RDoc to 6.9 until sdoc is fixed

Author: zzak

Gemfile

@@ -63,7 +63,7 @@ end
 
 group :doc do
   gem "sdoc", git: "https://github.com/rails/sdoc.git", branch: "main"
-  gem "rdoc", "~> 6.7"
+  gem "rdoc", "< 6.10"
   gem "redcarpet", "~> 3.2.3", platforms: :ruby
   gem "w3c_validators", "~> 1.3.6"
   gem "rouge"

Gemfile.lock

@@ -713,7 +713,7 @@ DEPENDENCIES
   rack-cache (~> 1.2)
   rails!
   rake (>= 13)
-  rdoc (~> 6.7)
+  rdoc (< 6.10)
   redcarpet (~> 3.2.3)
   redis (>= 4.0.1)
   redis-namespace