Fix time issue in AccessInfo test
Fix time issue in AccessInfo test

I've only seen this happen once, however by making the token expiry 5
minutes in the future, then checking that it wont have expired in 300
seconds means that if the test happens all on the same second boundary
then the test will fail.

Just increase the time we're checking for by a second to ensure it
doesn't happen.

Change-Id: Iadeadfbacaf6f1b939c237919b52445c60c9bdd0

magic0704/python-keystoneclient,Mercador/python-keystoneclient,darren-wang/ksc,magic0704/python-keystoneclient,darren-wang/ksc,sdpp/python-keystoneclient,klmitch/python-keystoneclient,sdpp/python-keystoneclient,Mercador/python-keystoneclient,klmitch/python-keystoneclient