Release container images manually from the latest version on PyPI

[Lawouach]

Summary

The 1.21.1 release published to PyPI, but the container job gave up after 5 minutes: PyPI's JSON API listed 1.21.1 while the index pip reads still stopped at 1.21.0, for well over 15 minutes.

• Manual run (workflow_dispatch): packages the latest chaostoolkit that pip can actually install from PyPI, or the version given in the new optional version input. The image is tagged latest and with that version, as before.
• Release run (workflow_call from release.yaml): unchanged, it packages the release tag.
• The wait for the version to be installable goes from 5 to 20 minutes.
• Inputs are passed through environment variables, not interpolated into the script.

Usage

gh workflow run containers.yaml                       # latest on PyPI
gh workflow run containers.yaml -f version=1.21.1     # a given version

Testing

• actionlint clean.
• The version lookup (pip download --no-deps chaostoolkit, then reading the wheel's name) run locally gives the version pip installs.

[github-actions]

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