No scan all policy if Clair is not installed.
No scan all policy if Clair is not installed.

This commit fixes #5283 by not registering scan all policy when Harbor
is not deployed with Clair.

wy65701436/harbor,steven-zou/harbor,wy65701436/harbor,wy65701436/harbor,steven-zou/harbor,reasonerjt/harbor,steven-zou/harbor,wy65701436/harbor,steven-zou/harbor,reasonerjt/harbor,wy65701436/harbor,reasonerjt/harbor,reasonerjt/harbor,wy65701436/harbor,steven-zou/harbor,reasonerjt/harbor,steven-zou/harbor,reasonerjt/harbor