Prevent race condition in buildpack update commits to cf-release
Prevent race condition in buildpack update commits to cf-release

Reference: https://cloudfoundry.slack.com/archives/buildpacks/p1468347010000695

Signed-off-by: James Wen <3b2f4c88287a5fcd7db73a67dd1ab82807db04ee@columbia.edu>

cloudfoundry/buildpacks-ci,cloudfoundry/buildpacks-ci,cloudfoundry/buildpacks-ci,cloudfoundry/buildpacks-ci,orange-cloudfoundry/buildpacks-ci,orange-cloudfoundry/buildpacks-ci,orange-cloudfoundry/buildpacks-ci,cloudfoundry/buildpacks-ci