`benchmarks/lobsters` is not working with Ruby 4.1.0.dev

[hsbt]

https://github.com/ruby/ruby/actions/runs/20513074051/job/58936516732

Because commonmarker = 1.0.0.pre depends on Ruby ~> 3.1
and commonmarker >= 1.0.0.pre, < 1.0.0.pre.2 depends on Ruby >= 3.1, <
3.2.dev,
  commonmarker >= 1.0.0.pre, < 1.0.0.pre.2 requires Ruby >= 3.1, < 4.A.

I temporary disabled lobsters benchmark at ruby/ruby now.

ruby/ruby@565ea26