Update license in pyproject.toml (#954)

* Update license in pyproject.toml

* Aktualisieren von CHANGELOG.md

Author: adtzlr

CHANGELOG.md

@@ -8,6 +8,9 @@ All notable changes to this project will be documented in this file. The format
 - Add `Mesh.clear_points_without_cells()` to clear the list of points without cells (useful for center-points of multi-point constraints).
 - Release FElupe on conda-forge, starting with v9.2.0.
 
+### Fixed
+- Fix the declaration of the (spdx identifier) license and license-file in `pyproject.toml`.
+
 ## [9.2.0] - 2025-03-04
 
 ### Added

pyproject.toml

@@ -15,7 +15,8 @@ authors = [
 
 ]
 requires-python = ">=3.9"
-license = {file = "LICENSE"}
+license = "GPL-3.0-or-later"
+license-files = ["LICEN[CS]E.*"]
 keywords = [
   "computational-mechanics",
   "fea",
@@ -34,7 +35,6 @@ classifiers = [
   "Development Status :: 5 - Production/Stable",
   "Programming Language :: Python",
   "Intended Audience :: Science/Research",
-  "License :: OSI Approved :: GNU General Public License v3 or later (GPLv3+)",
   "Operating System :: OS Independent",
   "Programming Language :: Python",
   "Programming Language :: Python :: 3",