Fix a typo in db/catalog/api.py
Fix a typo in db/catalog/api.py

a typo frn --> fqn

Change-Id: I8c16a7fd5b784e19dd296be339358415d1fb0710

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