v2.50.0

Features

• add KIX region to image_uris

Bug Fixes and Other Changes

• Rename PredictorBase.delete_endpoint as PredictorBase.delete_predictor
• incorrect default argument for callback output parameter

Documentation Changes

• Remove years from copyright boilerplate
• Fix documentation formatting for PySpark and SparkJar processors

Testing and Release Infrastructure

• enable py38 tox env