[python] Fix poetry deprecation warnings

[4c0n]

Since the release of Poetry 2.0.0 the format of pyproject.toml that it is expecting changed.
See also: https://python-poetry.org/blog/announcing-poetry-2.0.0

This PR aims to update the pyproject.toml file to a format that does not use (now) deprecated features introduced by Poetry 1.

PR checklist

• Read the contribution guidelines.
• Pull Request title clearly describes the work in the pull request and Pull Request description provides details about how to validate the work. Missing information here may result in delayed response from the community.
• Run the following to build the project and update samples:

  ./mvnw clean package || exit
  ./bin/generate-samples.sh ./bin/configs/*.yaml || exit
  ./bin/utils/export_docs_generators.sh || exit
  

  (For Windows users, please run the script in WSL)
  Commit all changed files.
  This is important, as CI jobs will verify all generator outputs of your HEAD commit as it would merge with master.
  These must match the expectations made by your contribution.
  You may regenerate an individual generator by passing the relevant config(s) as an argument to the script, for example ./bin/generate-samples.sh bin/configs/java*.
  IMPORTANT: Do NOT purge/delete any folders/files (e.g. tests) when regenerating the samples as manually written tests may be removed.
• File the PR against the correct branch: master (upcoming 7.x.0 minor release - breaking changes with fallbacks), 8.0.x (breaking changes without fallbacks)
• If your PR is targeting a particular programming language, @mention the technical committee members, so they are more likely to review the pull request. (@cbornet @tomplus @krjakbrjak @fa0311 @multani)

[wing328]

thanks for the pr

is the change backward compatible with poetry 1.x?

[4c0n]

thanks for the pr

is the change backward compatible with poetry 1.x?

Hi @wing328, It is not backwards compatible with Poetry 1.x.
We haven't seen a 1.x release since December 6, 2024 and there has not been active development on 1.x since the release of 2.0, which has seen regular releases since: https://github.com/python-poetry/poetry/releases

That is also why I added this line: https://github.com/4c0n/openapi-generator/blob/b554c1bc3adc621f144c46112b6a00a526e59246/modules/openapi-generator/src/main/resources/python/pyproject.mustache#L32

If people are still using 1.x I'd say it's about time to upgrade or use an older version of the generator as well😄.

[wing328]

for the upcoming release v7.14.0, we only allow breaking changes with fallbacks only.

can we add an option (default to false) to let users fallback to poetry 1.x?

[4c0n]

@wing328 I added a fallback option, hope this is sufficient?
When would we be allowed to drop support for Poetry 1.x?

[wing328]

if no one has feedback/question on this pr, i'll merge it later this week

[wing328]

fyi. merged #21328 to update samples with a test

[4c0n]

Thank you @wing328 :)