add test for question delete; fix bug with delete question

web/src/components/IntentDetails.js

@@ -72,7 +72,7 @@ class IntentDetails extends Component {
                 rightIcon={
                   <SVGIcon
                     onClick={() => {
-                      this.deleteQuestion (question);
+                      this.deleteQuestion (index);
                     }}
                   >
                     {' '}
@@ -146,12 +146,10 @@ class IntentDetails extends Component {
     this.setState ({intent: newIntent});
   }
 
-  deleteQuestion (question) {
+  deleteQuestion (index) {
     if (this.state.intent.questions.length > 1) {
       let newIntent = this.state.intent;
-      let removeId = newIntent.questions.indexOf (question);
-      if (removeId !== -1) newIntent.questions.splice (removeId, 1);
-
+      if (index >= 0 && index < newIntent.questions.length) newIntent.questions.splice (index, 1);
       this.setState ({intent: newIntent});
     }
   }