Minor tweaks for parsing/unparsing ReqIF files produced by Polarion

What's Changed

• pyproject: remove Poetry by @stanislaw in #84
• Code climate: tasks: add ruff linter by @stanislaw in #83
• tasks: update release task by @stanislaw in #85
• tests/integration: add an example produced from Polarion by @stanislaw in #86
• Bump version to 0.0.24 by @stanislaw in #89

Full Changelog: 0.0.23...0.0.24