Fix duplicate install of config.py in meson build

Author: antonio-rojas

src/sage/meson.build

@@ -86,7 +86,6 @@ foreach package : no_processing
 endforeach
 
 py.install_sources(
-  config_file,
   'all.py',
   'all__sagemath_bliss.py',
   'all__sagemath_categories.py',