Description of problem:
The action: delete watchdog from template failed with the following error: 
[Cannot ${action} ${type}. VM is not found.]


Version-Release number of selected component (if applicable):
vdsm-4.17.3-1.el7ev.noarch
Red Hat Enterprise Virtualization Manager Version: 3.6.0-0.12.master.el6

How reproducible:
100%

Steps to Reproduce:
1.send delete request in REST API: https://10.35.161.33/api/templates/<tempalte id>/watchdogs/00000000-0000-0000-0000-000000000000
2.
3.

Actual results:
[Cannot ${action} ${type}. VM is not found.]
Version-Release number of selected component (if applicable):

Expected results:
the action should work

Additional info:
link to automation test: 
https://rhev-jenkins.rhev-ci-vms.eng.rdu2.redhat.com/job/3.6-GE-Tier1/7/testReport/junit/rhevmtests.sla.watchdog.watchdog_test/331-WatchdogCRUDTemplate_REST;test_remove_watchdog_template/WatchdogCRUDTemplate_REST_test_remove_watchdog_template/