PEP 639 compliance (#378)

Author: DimitriPapadopoulos

pyproject.toml

@@ -1,5 +1,5 @@
 [build-system]
-requires = ["setuptools>=64"]
+requires = ["setuptools>=77.0.3"]
 build-backend = "setuptools.build_meta"
 
 [project]
@@ -16,11 +16,11 @@ maintainers = [
     { name = "Markus D. Herrmann" },
     { name = "Christopher P. Bridge" },
 ]
-license = { text = "LICENSE" }
+license = "MIT"
+license-files = [ "LICENSE" ]
 classifiers = [
     "Development Status :: 4 - Beta",
     "Intended Audience :: Science/Research",
-    "License :: OSI Approved :: MIT License",
     "Operating System :: MacOS",
     "Operating System :: Microsoft :: Windows",
     "Operating System :: POSIX :: Linux",