fixtures: offline tests must not use a version not
fixtures: offline tests must not use a version not

...supplied by the buildpack.

See https://github.com/rubygems/rubygems/pull/4076

cloudfoundry/ruby-buildpack,cloudfoundry/ruby-buildpack,cloudfoundry/ruby-buildpack,cloudfoundry/ruby-buildpack,cloudfoundry/ruby-buildpack