Officially support Python 3.15

Author: mdmintz

setup.py

@@ -142,6 +142,7 @@
         "Programming Language :: Python :: 3.12",
         "Programming Language :: Python :: 3.13",
         "Programming Language :: Python :: 3.14",
+        "Programming Language :: Python :: 3.15",
         "Topic :: Internet",
         "Topic :: Internet :: WWW/HTTP :: Browsers",
         "Topic :: Scientific/Engineering",