Including modules creates an infinite loop between methods

Hi! I think RDoc sometimes wrongly infers module ancestry and then methods can have cyclical see references.

I encountered this error in the docs for GrpahQL-Ruby (fix: https://github.com/rmosolgo/graphql-ruby/pull/4819) and I created this script to replicate it:

# rdoc_bug.rb
module DoSomething
  def self.generate_module
    Module.new do
      include DoSomethingExtra
    end
  end

  def do_something
    1 + 1
  end

  module DoSomethingExtra
    include DoSomething

    def do_something
      super + 1
    end
  end
end

For me, that script ends in "stack level too deep":

$ rdoc rdoc_bug.rb
Parsing sources...
100% [ 1/ 1]  rdoc_bug.rb

Generating Darkfish format into /Users/rmosolgo/code/graphql-ruby/doc...
uh-oh! RDoc had a problem:
stack level too deep

run with --debug for full backtrace

I was able to work around it, so this bug is not blocking me, but I thought I'd open it here in case its helpful to anyone else.

Start with the supplied rdoc_bug.rb reproducer and run rdoc rdoc_bug.rb; use --debug to trace the recursive documentation path. Inspect the ancestry and method cross-reference handling involved in the cyclical see references, and consider the issue done when this example completes without a stack overflow while preserving the generated documentation.