MAINT: PEP 639 complicance

Author: DimitriPapadopoulos

pyproject.toml

@@ -7,15 +7,15 @@ name = "niworkflows"
 dynamic = ["version"]
 description = "NeuroImaging Workflows provides processing tools for magnetic resonance images of the brain."
 readme = "README.rst"
-license = {file = "LICENSE"}
+license = "Apache-2.0"
+license-files = ["LICENSE"]
 requires-python = ">= 3.9"
 authors = [
     { name = "The NiPreps Developers", email = "[email protected]" },
 ]
 classifiers = [
     "Development Status :: 4 - Beta",
     "Intended Audience :: Science/Research",
-    "License :: OSI Approved :: Apache Software License",
     "Programming Language :: Python :: 3.9",
     "Programming Language :: Python :: 3.10",
     "Programming Language :: Python :: 3.11",