Fix one more optional test

Author: antonio-rojas

src/sage/doctest/control.py

@@ -1489,7 +1489,7 @@ def run(self):
             Using --optional=sage
             Features to be detected: ...
             Doctesting 1 file.
-            sage -t ....py
+            ....py
                 [4 tests, ...s wall]
             ----------------------------------------------------------------------
             All tests passed!