src/sage/doctest/control.py: Update doctest output

Author: Matthias Koeppe

src/sage/doctest/control.py

@@ -717,7 +717,7 @@ def add_files(self):
             sage: DD = DocTestDefaults(all=True, logfile=log_location)
             sage: DC = DocTestController(DD, [])
             sage: DC.add_files()
-            Doctesting entire Sage library.
+            Doctesting ...
             sage: os.path.join(SAGE_SRC, 'sage') in DC.files
             True