attempt to fix broken python CI job
diff --git a/setup.py b/setup.py
index 970c6ee..57bbc1d 100644
--- a/setup.py
+++ b/setup.py
@@ -49,6 +49,8 @@
             os.path.dirname(self.get_ext_fullpath(ext.name)))
         cmake_args =  ['-DCMAKE_LIBRARY_OUTPUT_DIRECTORY=' + extdir]
         cmake_args += ['-DWITH_PYTHON=True']
+        # CI was failing; this should help find the right python version
+        cmake_args += ['-DPYTHON_EXECUTABLE=' + sys.executable]
         cfg = 'Debug' if self.debug else 'Release'
         build_args = ['--config', cfg]