Openseries

- Adjustments to meet demands of new Poetry version 2.0.1, among them format changes to pyproject.toml
- Set strict=True in all uses of zip()
- Set arguments in console example and changed position of code sample into badge at top in README.md
- Some widening of test in test_package.py
- Refactored folder name types -> owntypes to adhere to [A005](https://docs.astral.sh/ruff/rules/stdlib-module-shadowing/) error in ruff updated to ver 0.9.2. This is a *POTENTIALLY BREAKING CHANGE*.

- adjustments to make typing work with new version of numpy
- Removed strict type DatabaseIdStringType on database identifiers and replaced with regular string
- checks that project still work with updated dependencies
- some tooling updates in github scripts

- Checked and project works with Python 3.13. Project meta data changed to this effect.
- Development updates only otherwise. E.g. adapting to changes in ruff, pandas-stubs etc.

- Changed worst_month() to be consistent with resample_to_business_period_ends().
- Updated Poetry to version 1.8.4.
- Miscellaneous dependency and lockfile updates.

- Added pandas .ffill() as precursor to all remaining pct_change() to suppress pandas FutureWarnings in dependent projects.

- Tightened existing checks to not allow mixed series types as methods input. The coverage level of the checks has not been widened.
- Added pandas .ffill() as precursor to pct_change() to suppress pandas FutureWarnings in dependent projects.
- Fixed method .resample_to_business_period_ends() so it considers renamed labels.
- Corrected warning in this changelog for release of version 1.7.0. Added 'NO'.
- Miscellaneous dependency and lockfile updates.