bump vizzini
bump vizzini

[finishes #153472482]

Submodule src/code.cloudfoundry.org/vizzini b9169526..47486897:
  > update the checksum of the tarball

Signed-off-by: John Shahid <d5f6a919b5b5e6a4f7f09f1adf45e90e5c38b58e@gmail.com>

cloudfoundry-incubator/diego-release,cloudfoundry-incubator/diego-release,cloudfoundry-incubator/diego-release,cloudfoundry-incubator/diego-release