Fix python-requires to 3.12 (#5)

Path.walk was introduced in python 3.12 
and it is used in the library.

Author: OriolAbril

pyproject.toml

@@ -10,7 +10,7 @@ authors = [
 description = "Generate Python stub files (PYI) from docstrings"
 readme = "README.md"
 license.file = "LICENSE"
-requires-python = ">=3.10"
+requires-python = ">=3.12"
 classifiers = [
   "Development Status :: 1 - Planning",
   "Intended Audience :: Developers",