Close objects in remote test

Author: snbianco

astroquery/mast/tests/test_mast_remote.py

@@ -464,6 +464,7 @@ def test_missions_workflow(self, tmp_path, mission, query_params):
         if mission == 'roman' and asdf is not None:
             assert isinstance(obj, asdf.AsdfFile)
         assert isinstance(obj, fits.HDUList)
+        obj.close()
 
     ###################
     # MastClass tests #