feat: drop py2 support / add black and poetry

[octavian-ionescu]

Resolves FT-1f648001-844c-4667-8252-8d8ed9e23d87

• I have added automatic tests where applicable.
• The PR contains a description of what has been changed.
• The description contains manual test instructions.
• The PR contains updates to the release notes.
• I have verified that the documentation is still up to date.

Changes

• added black;
• dropped support for python 2.7, 3.6 and 3.7;
• added python 3.12 support;
• switched to poetry;
• cicd improvements.