fix(service): add missing gems

[joseivanlopez]

Problem

csv does not belong to the ruby standard library since ruby 3.4. The gem is still installed as part of the ruby 3.4 package, but the CI task for running unit tests fails because the code is executed via bundle.

Solution

Add the required gems to the gemspec file.

[joseivanlopez]

See https://github.com/agama-project/agama/actions/runs/12787544752/job/35646933299?pr=1898

/usr/lib64/ruby/gems/3.4.0/gems/fast_gettext-2.3.0/lib/fast_gettext/vendor/mofile.rb:171: warning: prime was loaded from the standard library, but is not part of the default gems starting from Ruby 3.1.0.
You can add prime to your Gemfile or gemspec to silence this warning.
/usr/lib64/ruby/vendor_ruby/3.4.0/yast/i18n.rb:2: warning: logger 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 logger to your Gemfile or gemspec to silence this warning.
/usr/lib64/ruby/vendor_ruby/3.4.0/yast/exportable.rb:1: warning: ostruct 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 ostruct to your Gemfile or gemspec to silence this warning.
/usr/share/YaST2/lib/yast2/fs_snapshot.rb:31: warning: csv was loaded from the standard library, but is not part of the default gems starting from Ruby 3.4.0.
You can add csv to your Gemfile or gemspec to silence this warning.

An error occurred while loading ./test/agama/autoyast/converter_test.rb.
Failure/Error: kernel_class.send(:no_warning_require, name)

LoadError:
  cannot load such file -- csv
# ./test/test_helper.rb:43:in 'Kernel#require'
# /usr/share/YaST2/lib/yast2/fs_snapshot.rb:31:in '<top (required)>'