Fix tests for Python 2.7

tests/console/commands/test_check.py

@@ -36,6 +36,7 @@ def test_check_invalid(app, mocker):
 Error: u'description' is a required property
 Error: INVALID is not a valid license
 Warning: A wildcard Python dependency is ambiguous. Consider specifying a more explicit one.
+Warning: The "pendulum" dependency specifies the "allows-prereleases" property, which is deprecated. Use "allow-preleases" instead.
 """
     else:
         expected = """\