Fix crash when execing invalid RPC

When executing an invalid RPC, the temporary datastore wasn't being
properly canceled.

Issue: https://tree.taiga.io/project/jktjkt-netconf-cli/issue/209
Change-Id: I56e301c509781275bd960f4cd846d649507a875d
diff --git a/tests/example-schema.yang b/tests/example-schema.yang
index 0db4c4f..44baf80 100644
--- a/tests/example-schema.yang
+++ b/tests/example-schema.yang
@@ -167,6 +167,15 @@
 
     rpc noop {}
 
+    rpc setIp {
+      input {
+        leaf ip {
+          mandatory true;
+          type string;
+        }
+      }
+    }
+
     list selectedNumbers {
         key 'value';
         leaf value {