Remove mistral libs installation from test-hooks
Remove mistral libs installation from test-hooks

After the https://review.openstack.org/#/c/225960/ landed, we need to
remove mistral libs installation to devstack.

Change-Id: I1824f9dd026fdc016d5a34292542d13d393ba566
Related-Bug: #1497913

openstack/murano,DavidPurcell/murano_temp,olivierlemasle/murano,satish-avninetworks/murano,NeCTAR-RC/murano,olivierlemasle/murano,satish-avninetworks/murano,DavidPurcell/murano_temp,olivierlemasle/murano,satish-avninetworks/murano,openstack/murano,NeCTAR-RC/murano,NeCTAR-RC/murano,olivierlemasle/murano,DavidPurcell/murano_temp,satish-avninetworks/murano,DavidPurcell/murano_temp,NeCTAR-RC/murano