Gate Python dependencies
Gate Python dependencies

The plan is to remove python dependencies, so this makes the first step
of not requiring it for bootstrap.

The goal is that a user can do this:

BUILD_PYTHON=0 ./bootstrap.sh
source dev.env
make
./tools/unit_test_runner.sh

This only runs unit tests, but in future Go-based end-to-end testing is
planned.

Signed-off-by: Morgan Tocker <cfa41afc5ac20f7c1e01316e2d765e1ba4c4bf7a@gmail.com>

mahak/vitess,mahak/vitess,tinyspeck/vitess,vitessio/vitess,mahak/vitess,tinyspeck/vitess,vitessio/vitess,mahak/vitess,mahak/vitess,mahak/vitess,tinyspeck/vitess,tinyspeck/vitess,vitessio/vitess,vitessio/vitess,tinyspeck/vitess,vitessio/vitess,vitessio/vitess,tinyspeck/vitess,vitessio/vitess,mahak/vitess,tinyspeck/vitess,vitessio/vitess,mahak/vitess