Revert "Revert "Migrate ./driver.py to Python 3""
Revert "Revert "Migrate ./driver.py to Python 3""

This reverts commit 180ac090e71d7b1a54e56c1b0942ec43939cea36.

Parts of our infra were updated to provide Python 3. Let's give this
another try.

rabbitmq/rabbitmq-website,rabbitmq/rabbitmq-website,rabbitmq/rabbitmq-website,rabbitmq/rabbitmq-website,rabbitmq/rabbitmq-website