Bump jruby brats test memory to 2G
Bump jruby brats test memory to 2G

Co-authored-by: Andrew Meyer <8f92422f5861fc9f31873f75dd770facd670512b@pivotal.io>

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