Manually upgrade the metadata in pyproject.toml

Author: Pierre-Sassoulas

pyproject.toml

@@ -29,10 +29,11 @@ classifiers = [
   "Operating System :: POSIX",
   "Operating System :: Microsoft :: Windows",
   "Operating System :: MacOS :: MacOS X",
-  "Programming Language :: Python :: 3.8",
   "Programming Language :: Python :: 3.9",
   "Programming Language :: Python :: 3.10",
   "Programming Language :: Python :: 3.11",
+  "Programming Language :: Python :: 3.12",
+  "Programming Language :: Python :: 3.13",
   "Programming Language :: Python :: Implementation :: CPython",
   "Programming Language :: Python :: Implementation :: PyPy",
   "Topic :: Software Development :: Quality Assurance",