0.24.0

• Upgraded SQLAlchemy support to 1.3.
• Added backoff_factor in connection to configure retry interval.
• Added official Python 3.8 support.
• Made it so that the SQLAlchemy dialect is now aware of the return type of the
  date_trunc function.
• Added driver attribute, as SQLAlchemy relies on interfaces having that string for identification.

Full Changelog: 0.23.2...0.24.0