Fix neutron auth issue
Fix neutron auth issue

Adding admin role to the new_user for the new tenant
It will fix this bug for other tests based on this class

JIRA: FUNCTEST-734

Change-Id: Ia3b8797fa391f528d24425a5b13c1b329cb992f4
Signed-off-by: boucherv <92505b05743740ff7910a3d93741c58e8604a7fb@orange.com>

opnfv/functest,mywulin/functest,mywulin/functest,opnfv/functest