Add Trove classifier for Python 3.13 (#150)

Author: AA-Turner

src/trove_classifiers/__init__.py

@@ -495,6 +495,7 @@
     "Programming Language :: Python :: 3.10",
     "Programming Language :: Python :: 3.11",
     "Programming Language :: Python :: 3.12",
+    "Programming Language :: Python :: 3.13",
     "Programming Language :: Python :: Implementation",
     "Programming Language :: Python :: Implementation :: CPython",
     "Programming Language :: Python :: Implementation :: IronPython",