Add Python v3.14 support and drop Python v3.9

Python 3.14 pre-releases

• Set up v3.14 test job
  • With allow_failure: true, to allow tests to fail

Python 3.14 stable release

• Handle deprecation warning and breaking features:
  • When distributing Silkaj v0.20 with py-substrate-sdk, its dependency py-sr25519 does not provide Py3.14 wheel. I could circumvent the issue locally by setting the environment variable mentioned in the ticket. But this is not a long term solution. A solution has to be found.
  • For some reasons on my local environment, I get click v8.3.0 (v8.2.0) installed as a transitive dependency of rich-click. It should not install higher than click v8.1.8, since v8.2.0 requires Py3.9 support to be dropped. g1_monetary_license tests are failing.
• Remove allow_failure: true, now on the tests should pass

Drop Python 3.9 support

• Delete test job for v3.9 from .gitlab-ci.yml
• pyproject.toml: Bump minimum versions:
  • tools.poetry.dependency.python
  • remove tools.ruff.target-version
    • v0.20 branch: apply changes after the porting to avoid conflicts with current developments
    • v0.12 branch: apply changes?

Post

• Open follow-up v3.10/3.15 ticket: Add Python v3.15 support and drop Python v3.10 (#508)

References

• Expected to be release the October 7th 2025.
• Introduce 3.14 and drop 3.9 Python image genera... (docker/python3/poetry#12 - closed)