MINOR: Update version of docker-utils to v0.0.40-python2 and pip to latest py27 supported version

[andrewegel]

confluent-docker-utils tag v0.0.40-python2 update evicts some needless dependencies for runtime, and updates a couple of python modules to their latest python2 supported version.

Deprecation Notice

This is used for building images for version 4.1.x or lower, and should not be used for adding new images.

For the 5.4.0 release and greater the images have been migrated to the following repositories:

• common-docker
• control-center-images
• kafkacat-images
• kafka-images
• kafka-mqtt-images
• kafka-replicator-images
• kafka-rest-images
• kafka-streams-examples
• ksql-images
• schema-registry-images