Merge branch 'dd/ci-swap-azure-pipelines-with-github-actions'

Update the CI configuration to use GitHub Actions, retiring the one based on Azure Pipelines. * dd/ci-swap-azure-pipelines-with-github-actions: ci: let GitHub Actions upload failed tests' directories ci: add a problem matcher for GitHub Actions tests: when run in Bash, annotate test failures with file name/line number ci: retire the Azure Pipelines definition README: add a build badge for the GitHub Actions runs ci: configure GitHub Actions for CI/PR ci: run gem with sudo to install asciidoctor ci: explicit install all required packages ci: fix the `jobname` of the `GETTEXT_POISON` job ci/lib: set TERM environment variable if not exist ci/lib: allow running in GitHub Actions ci/lib: if CI type is unknown, show the environment variables