Update rspec-mocks in QA directory for Ruby 3.2

What does this MR do and why?

In the Ruby 3.2 pipeline (https://gitlab.com/gitlab-org/gitlab/-/jobs/5854231602), some tests were failing due to an issue fixed in rspec-mocks 3.12.6: https://github.com/rspec/rspec-mocks/issues/1523

How to set up and validate locally

From the qa directory, run this with Ruby 3.2 (you can add ruby 3.2.2 in .tool-versions):

bundle exec rspec -O .rspec_internal ./spec/tools/reliable_report_spec.rb