Ruby 3 changed the way keyword arguments work.
Currently, to forward arguments, the only way that works in Ruby 2.6, 2.7, and 3.0,
is to call `ruby2_keywords :method_name` for the method that receives the arguments.

This will cause Ruby to remember that the final hash was created by keyword arguments,
and then when expanding out the arguments later, eg [here](https://github.com/rspec/rspec-expectations/blob/43bf64b01f8356979ffbc373b2e81d2ab1389b29/lib/rspec/matchers/built_in/has.rb#L67),
it will see that the last element was created by keywords, and it will pass that into
the keywords area of a method infocation.

If we don't do this, it will consider it an ordinal argument and not line it up with
the keywords. This typically causes a "wrong number of arguments" error, because it's
passing an extra ordinal argument.

Here is another example from within RSpec, where they have arrived at this solution
for the same problem: https://github.com/rspec/rspec-expectations/blob/43bf64b01f8356979ffbc373b2e81d2ab1389b29/lib/rspec/matchers/dsl.rb#L538-L540

Co-authored-by: Jon Rowe <mail@jonrowe.co.uk>

Co-authored-by: Jon Rowe <mail@jonrowe.co.uk>