MINIFICPP-1641 Parallelization of docker tests

[martinzink]

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[szaszm]

Interestingly, the Github Actions CI checks didn't run on this PR. Is it turned off somewhere, or was it just the Github Infra having trigger issues again?

edit: Looking at the checks tab, a new action is blocked. Submitted infra ticket to enable the blocked action: https://issues.apache.org/jira/browse/INFRA-24603

phoenix-actions/test-reporting@v12 is not allowed to be used in apache/nifi-minifi-cpp. Actions in this workflow must be: within a repository owned by apache, created by GitHub, verified in the GitHub Marketplace, or matching the following: */*@[a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9][a-f0-9]+, AdoptOpenJDK/install-jdk@*, JamesIves/github-pages-deploy-action@5dc1d5a192aeb5ab5b7d5a77b7d36aea4a7f5c92, TobKed/label-when-approved-action@*, actions-cool/issues-helper@*, actions-rs/*, al-cheb/configure-pagefile-action@*, amannn/action-semantic-pull-request@*, apache/*, burrunan/gradle-cache-action@*, bytedeco/javacpp-presets/.github/actions/*, chromaui/action@*, codecov/codecov-action@*, conda-incubator/setup-miniconda@*, container-tools/kind-action@*, container-tools/microshift-action@*, dawidd6/action-download-artifact@*, delaguardo/setup-graalvm@*, docker://jekyll/jekyll:*, docker://pandoc/core:2.9, eps1lon/actions-label-merge-conflict@*, gaurav-nelson/github-action-markdown-li...

added in ci.yml:352

[szaszm]

force pushed a different commit with identical contents to trigger the CI workflow