Update tests and whatsnew for the 'quiet' flag

Doc/whatsnew/3.2.rst

@@ -383,7 +383,14 @@ Some smaller changes made to the core Python language are:
   (Suggested by Mark Dickinson and implemented by Eric Smith in :issue:`7094`.)
 
 * The interpreter can now be started with a quiet option, ``-q``, to suppress
-  the copyright and version information in an interactive mode.
+  the copyright and version information in an interactive mode.  The option can
+  be introspected using the :attr:`sys.flags` attribute::
+
+    $ python -q
+    >>> sys.flags
+    sys.flags(debug=0, division_warning=0, inspect=0, interactive=0,
+    optimize=0, dont_write_bytecode=0, no_user_site=0, no_site=0,
+    ignore_environment=0, verbose=0, bytes_warning=0, quiet=1)
 
   (Contributed by Marcin Wojdyr in issue:`1772833`).
 

Lib/test/test_sys.py

@@ -501,7 +501,7 @@ class SysModuleTest(unittest.TestCase):
         attrs = ("debug", "division_warning",
                  "inspect", "interactive", "optimize", "dont_write_bytecode",
                  "no_user_site", "no_site", "ignore_environment", "verbose",
-                 "bytes_warning")
+                 "bytes_warning", "quiet")
         for attr in attrs:
             self.assertTrue(hasattr(sys.flags, attr), attr)
             self.assertEqual(type(getattr(sys.flags, attr)), int, attr)