Fixes JS linting error
Fixes JS linting error

This patch fixes a JS linting error.  Errors should not be allowed, even
if the gate is broken.

Change-Id: Ib70ce346f0d2eff44a1e2db51d9b37cd251b78fb
Closes-Bug: 1596061

coreycb/horizon,openstack/horizon,ChameleonCloud/horizon,openstack/horizon,sandvine/horizon,ChameleonCloud/horizon,sandvine/horizon,bac/horizon,wolverineav/horizon,yeming233/horizon,bac/horizon,NeCTAR-RC/horizon,BiznetGIO/horizon,yeming233/horizon,yeming233/horizon,coreycb/horizon,BiznetGIO/horizon,ChameleonCloud/horizon,yeming233/horizon,bac/horizon,NeCTAR-RC/horizon,noironetworks/horizon,coreycb/horizon,wolverineav/horizon,noironetworks/horizon,BiznetGIO/horizon,NeCTAR-RC/horizon,openstack/horizon,coreycb/horizon,sandvine/horizon,NeCTAR-RC/horizon,noironetworks/horizon,noironetworks/horizon,wolverineav/horizon,sandvine/horizon,wolverineav/horizon,BiznetGIO/horizon,openstack/horizon,bac/horizon,ChameleonCloud/horizon