Migrate CircleCI from mozilla/cidockerbases:docker-latest

[jwhitlock]

We're planning to deprecate mozilla/cidockerbases by October 1, 2022. This image is used in the CircleCI build, which should change to a different image such as one of the Pre-Built CircleCI Docker Images. See mozilla/ci-docker-bases#322 for more context, and a list of other projects that have made the transition.

[jwhitlock]

🕘 We plan to stop updates to mozilla/cidockerbases:docker-latest image on October 1, 2022, less than 3 months away. This project uses this image in CircleCI. See mozilla/ci-docker-bases#322 for examples of projects that have successfully migrated away from mozilla/cidockerbases:docker-latest.

[jwhitlock]

🕘 We plan to stop updates to mozilla/cidockerbases:docker-latest image on October 1, 2022, less than 30 days away. This project uses this image in CircleCI. See mozilla/ci-docker-bases#322 for examples of projects that have successfully migrated away from mozilla/cidockerbases:docker-latest.

[jwhitlock]

We've now stopped updates to mozilla/cidockerbases:docker-latest.