bump garden-integration-tests
bump garden-integration-tests

[finishes #157752831]

Submodule src/code.cloudfoundry.org/garden-integration-tests d0cdd27..2d3e4c1:
  > Peas run with empty /etc/passwd when user is root

Co-authored-by: Claudia Beresford <80d58ba8cbfbf831cfa674a754c8439fd7d2f06e@pivotal.io>

cloudfoundry-incubator/guardian-release,cloudfoundry-incubator/guardian-release,cloudfoundry-incubator/guardian-release