ruby-mini-magick 4.11.0-1 autopkgtests failing on all arches (ruby error?)

[Łukasz Zemczak]

When looking at the recent tests for ruby-mini-magick against the new imagemagick, 12 test seem to be failing. But the failures look like this:

717s Failures:
717s
717s 1) With ImageMagick MiniMagick::Image.create creates an image
717s Failure/Error: expect(File.exists?(image.path)).to eq true
717s
717s NoMethodError:
717s undefined method `exists?' for File:Class
717s # ./spec/lib/mini_magick/image_spec.rb:127:in `block (5 levels) in <top (required)>'
717s # /usr/share/rubygems-integration/all/gems/webmock-3.18.1/lib/webmock/rspec.rb:37:in `block (2 levels) in <top (required)>'
(...)

Looks like maybe related to a new ruby version?
Example log: https://autopkgtest.ubuntu.com/results/autopkgtest-noble/noble/amd64/r/ruby-mini-magick/20240327_222302_1f696@/log.gz