Fixing malformed assert message formatting

This modification addresses Bug #1210296, specifically addressing
malformed assert message formatting in assert_called_anytime. When
verifying that an API method was called during test execution, the
assert statement used will throw a TypeError when formatting the
assert message, instead of the expected AssertionError. This occurs
because a nested tuple in the format list is not properly expanded.
The error itself likely exists because assert_called_anytime is not
currently used in the python-cinderclient testing framework.

The fix involves joining the arguments in the format list into a
single tuple, allowing proper argument expansion.

Fixes: bug 1210296

Change-Id: I6cf9dd55cff318e8a850637c540436c91dac08df

cinderclient/tests/fakes.py

@@ -67,7 +67,7 @@ class FakeClient(object):
                 break
 
         assert found, 'Expected %s %s; got %s' % (
-            expected, self.client.callstack)
+            expected + (self.client.callstack, ))
 
         if body is not None:
             try: