postcondition checks added in DELETE method for IndividualVNFSnapshot resource

SOL003/VNFLifecycleManagement-API/IndividualVNFSnapshot.robot

@@ -102,6 +102,7 @@ DELETE Individual VNF Snapshot
     ...    Post-Conditions: VNF Snapshot deleted
     DELETE individual VNF Snapshot
     Check HTTP Response Status Code Is    204
+    Check Postcondition VNF Snapshot Resource Is Deleted
 
 DELETE Individual VNF Snapshot - Conflict
      [Documentation]    Test ID: 7.3.1.41.9
@@ -114,4 +115,5 @@ DELETE Individual VNF Snapshot - Conflict
     ...    Post-Conditions: none
     DELETE individual VNF Snapshot - CONFLICT
     Check HTTP Response Status Code Is    409
-    Check HTTP Response Body Json Schema Is    ProblemDetails
\ No newline at end of file
+    Check HTTP Response Body Json Schema Is    ProblemDetails
+    Check Postcondition VNF Snapshot Resource Existence
\ No newline at end of file

SOL003/VNFLifecycleManagement-API/VnfLcmMntOperationKeywords.robot

@@ -1983,6 +1983,16 @@ DELETE individual VNF Snapshot - CONFLICT
     Delete    ${apiRoot}/${apiName}/${apiMajorVersion}/vnf_snapshots/${vnfSnapshotInfoId_InUse} 		
     ${outputResponse}=    Output    response
 	Set Global Variable    ${response}    ${outputResponse} 
+	
+Check Postcondition VNF Snapshot Resource Is Deleted
+    Get individual VNF Snapshot
+    Integer    response status    404
+    Log    VNF Snapshot Resource deleted
+    
+Check Postcondition VNF Snapshot Resource Existence
+    Get individual VNF Snapshot
+    Integer    response status    200
+    Log    VNF Snapshot Resource is not deleted
 
 POST VNF State Snapshot
     log    Trying to perform a POST. This method should not be implemented