[setup.py] Adding stubs recursively.

Author: mmmarinho

setup.py

@@ -81,7 +81,7 @@ def build_extension(self, ext):
               'dqrobotics.solvers',
               'dqrobotics-stubs'],
     package_data={
-        'dqrobotics-stubs': ["*.pyi"],
+        'dqrobotics-stubs': ["**/*.pyi"],
     },
     classifiers=[
         "Programming Language :: Python :: 3.10",