feat: mark py3.13 in metadata

Author: sanjayankur31

setup.cfg

@@ -13,12 +13,11 @@ classifiers=
     License :: OSI Approved :: GNU Lesser General Public License v3 (LGPLv3)
     Natural Language :: English
     Operating System :: OS Independent
-    Programming Language :: Python :: 3.7
-    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
     Topic :: Scientific/Engineering
 
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