Add fiddle to gemfile error

[bendangelo]

/home/bendangelo/.asdf/installs/ruby/3.3.5/lib/ruby/gems/3.3.0/gems/pycall-1.5.2/lib/pycall/libpython/finder.rb:2: warning: /home/bendangelo/.asdf/installs/ruby/3.3.5/lib/ruby/3.3.0/fiddle.rb was loaded from the standard library, but will no longer be part of the default gems starting from Ruby 3.5.0.
You can add fiddle to your Gemfile or gemspec to silence this warning.
Also please contact the author of pycall-1.5.2 to request adding fiddle into its gemspec.

[mrkn]

@bendangelo, Could you please make a pull request?

[bendangelo]

Done