Broken specs on EE master: undefined method `to_key' for :user:Symbol

As seen, e.g., here: https://gitlab.com/gitlab-org/gitlab-ee/-/jobs/19110259

 1) Help Pages when help page is customized should display custom help page text
     Failure/Error: @app.call(env)

     NoMethodError:
       undefined method `to_key' for :user:Symbol
       Did you mean?  to_query
     # ./lib/gitlab/middleware/readonly_geo.rb:30:in `call'
     # ./lib/gitlab/request_context.rb:18:in `call'
     # ./config/initializers/fix_local_cache_middleware.rb:9:in `call'
     # ./lib/gitlab/middleware/static.rb:9:in `call'
     # ./lib/gitlab/testing/request_blocker_middleware.rb:36:in `call'
     # ./spec/features/help_pages_spec.rb:64:in `block (3 levels) in <top (required)>'
     # ./spec/spec_helper.rb:96:in `block (2 levels) in <top (required)>'

A number of specs reliably fail on EE master, but pass on CE master, with this error.