Suppress pushd/popd output of sync-package-specs script.
Suppress pushd/popd output of sync-package-specs script.

Signed-off-by: Anoop Gopalakrishnan <4f949a96abb97371fe8105c271e218763e3b32cc@pivotal.io>

pivotal-cf/cred-alert,pivotal-cf/cred-alert