Fix referenced before assignment error if vdisk doesn't have a template (#875)
Fix referenced before assignment error if vdisk doesn't have a template (#875)

Signed-off-by: Khaled K. Badr <1df47e5ad390089ee76a4fc62e290ac9531ee49a@outlook.com>
zero-os/0-orchestrator,zero-os/0-orchestrator,zero-os/0-orchestrator,zero-os/0-orchestrator