chore(ci): switch to next-gen CircleCI's convenience images

[bednar]

Proposed Changes

The current images are deprecated and no longer supported:

• https://discuss.circleci.com/t/legacy-convenience-image-deprecation/41034?mkt_tok=NDg1LVpNSC02MjYAAAF_aZ4aQBMMtwIJatxoGz4de_IMPoNZJOUAhbHY2j7KD_4fR38oMpf0qFjUBd15_QNaVKiHbjM5WE0emhPAvcNcagGm1rnILLJptARAtBWPhtQ
• https://circleci.com/blog/announcing-our-next-generation-convenience-images-smaller-faster-more-deterministic/

Checklist

• CHANGELOG.md updated
• Rebased/mergeable
• mvn test completes successfully
• Commit messages are in semantic format
• Sign CLA (if not already signed)

[codecov-commenter]

Codecov Report

Merging #266 (0eafadd) into master (f1b0e7a) will not change coverage.
The diff coverage is n/a.

❗ Current head 0eafadd differs from pull request most recent head 4339acb. Consider uploading reports for the commit 4339acb to get more accurate results

@@            Coverage Diff            @@
##             master     #266   +/-   ##
=========================================
  Coverage     89.17%   89.17%           
  Complexity      473      473           
=========================================
  Files           145      145           
  Lines          5773     5773           
  Branches        272      272           
=========================================
  Hits           5148     5148           
  Misses          545      545           
  Partials         80       80           

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