Bump tests pointer

git shortlog
David Sabeti and Jennifer Hickey (1):
  Update yeti for buildpack changes

Jennifer Hickey and Tim Labeeuw (4):
  Optimize performance by not binding services after app
  deployment (causing an additional app stage)
  Remove the category support as buildpacks will only
  support switching version by modifying app
  Remove tests for autoreconfig disable, as it's
  opt-in in buildpack world.  Bump assets to
  include all buildpack changes
  Remove Erlang, PHP, Python tests for
  unsupported dev_setup

Matt Reider (1):
  Update README.md