Poetry-types

- Loosen dependency constraints for `tomlkit` and `packaging`

- Drop support for Python 3.7
- Drop support for Poetry 1.5
- Remove usage of deprecated module `semver` with Poetry 1.6

- Drop support for poetry <1.5.0

- lock poetry-core to <1.6.0

- allow packaging 23.0 as peer dependency

- Packages which aren't recognized by `poetry-types` as type-packages can be manually added/removed to the types section in the `pyproject.toml`