Add rubygems 3.0.2, remove rubygems 3.0.1
Add rubygems 3.0.2, remove rubygems 3.0.1

for stack(s) cflinuxfs2, cflinuxfs3 [#162898690]

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