Linearmodels

The version improves compatibility with changes in SciPy 1.14.

- Increased minimums:
- Python: 3.9
- formulaic: 1.0.0
- NumPy: 1.22.3
- SciPy: 1.8.0
- pandas: 1.4.0
- statsmodels: 0.13.0
- The key feature of this release is compatibility with NumPy 2.
linearmodels wheels are built using NumPy 2.0.0rc1 (or later) and
can run on any version of NumPy 1.22.3 or later, including NumPy
2.0.0.
- Improved compatibility with fuutre changes in pandas 3.0.0.

> [!NOTE]
> In order to use NumPy 2, the environment must consist of packages that
> have been built against NumPy 2.0.0rc1 or later.

This is a compatibility release.

* Compatibility with NumPy 2
* Compatibility with recent pandas releases

* Bumped the minimum formulaic to 0.6.5.
* Released wheels for Python 3.12.

* Fixed a bug that affected dropping absorbed regressors when using weights (546).
* Improved the licensing information (545).
* Improved compatibility with recent pandas (548).

This is a bug-fix release.

* Fixes a bug that can be encountered when collection observation data in panel models when some entities or time periods are missing.