[Fix #6624] Use older RubyGems & Bundler on Windows (#6628)
[Fix #6624] Use older RubyGems & Bundler on Windows (#6628)

RubyGems versions >=3 and Bundler versions >=2 are not compatible with Ruby 2.2.
We *could* probably install different RubyGems and Bundler versions for
different versions of Ruby, but I don't know how to do that on Windows. On Linux
something like this could be used:

    if $(ruby -e 'exit (RUBY_VERSION >= "2.3.0")')

Using older versions of RubyGems and Bundler is probably OK for now.
maxjacobson/rubocop,smakagon/rubocop,tdeo/rubocop,tejasbubane/rubocop,mikegee/rubocop,palkan/rubocop,tejasbubane/rubocop,smakagon/rubocop,jfelchner/rubocop,vergenzt/rubocop,rrosenblum/rubocop,vergenzt/rubocop,deivid-rodriguez/rubocop,vergenzt/rubocop,jmks/rubocop,bbatsov/rubocop,jmks/rubocop,palkan/rubocop,deivid-rodriguez/rubocop,bquorning/rubocop,jfelchner/rubocop,rrosenblum/rubocop,maxjacobson/rubocop,mikegee/rubocop,panthomakos/rubocop,bquorning/rubocop,bquorning/rubocop,panthomakos/rubocop,meganemura/rubocop,meganemura/rubocop,tdeo/rubocop,jmks/rubocop,tdeo/rubocop,meganemura/rubocop,tejasbubane/rubocop,mikegee/rubocop,jfelchner/rubocop,deivid-rodriguez/rubocop,bbatsov/rubocop,panthomakos/rubocop,palkan/rubocop,rrosenblum/rubocop,maxjacobson/rubocop