With TF 2.16, users of TFP-on-TF must install `tf-keras` in addition to `tensorflow` -- so this change adds a custom error message if `tf-keras` (or `tf-keras-nightly`) is not installed.
PiperOrigin-RevId: 614280621
This is due to travis-ci.org being deprecated.
One immediate advantage to the switch is that Github Actions has more powerful
machines which aren't shared across projects in an as obvious way as Travis
machines were. That said, they're not powerful enough to eschew test sharding
altogether.
PiperOrigin-RevId: 345051868