Add SPDX license identifier

Author: cdce8p

pyproject.toml

@@ -1,12 +1,14 @@
 [build-system]
-requires = ["hatchling", "hatch-vcs"]
+requires = ["hatchling>=1.27.0", "hatch-vcs"]
 build-backend = "hatchling.build"
 
 [tool.hatch.version]
 source = "vcs"
 
 [project]
 name = "jsonschema-specifications"
+license = "MIT"
+license-files = ["COPYING"]
 description = "The JSON Schema meta-schemas and vocabularies, exposed as a Registry"
 requires-python = ">=3.9"
 readme = "README.rst"
@@ -23,10 +25,8 @@ authors = [
 classifiers = [
   "Development Status :: 5 - Production/Stable",
   "Intended Audience :: Developers",
-  "License :: OSI Approved :: MIT License",
   "Operating System :: OS Independent",
   "Programming Language :: Python",
-  "Programming Language :: Python :: 3.8",
   "Programming Language :: Python :: 3.9",
   "Programming Language :: Python :: 3.10",
   "Programming Language :: Python :: 3.11",