title: dialog interrupted in middle of a prompt only resumes from beginning of the prompt step
body: <p>I am trying to design a dinner ordering bot. There is a 'orderDinner' dialog which has only two functions --> prompt text and process the response. In context of 'orderDinner' dialog, beginDialogAction is done for trigger 'alcohol'. It invokes a new dialog 'checkAge'. What I want is after checkAge is done and age is validated the 'orderDinner' dialog should be resume from step 2 but it always starts from step 1. Below is the code:</p>
  
  <pre><code>bot.dialog('orderDinner', [
  function (session, args){
      let promptmessage;
      if (args &amp;&amp; args.resumed == true) {
          promptmessage = 'What else would you like to add?';
      } else {
          promptmessage = 'What would you like to order today?';
      }
      promptmessage += '(_type done when no more items to add_)';
      builder.Prompts.text(session, promptmessage);
  },
  function (session, results, args) {
      session.send(`${results.response} added to dinner cart!`);
      session.replaceDialog('orderDinner', {
          resumed : true
      });
  }
  ]).beginDialogAction('checkAge', 'checkAge', {
      matches: /^alcohol$/i
  }).beginDialogAction('doneOrderDinner', 'doneOrderDinner', {
      matches: /^done$/i
  })
  
  bot.dialog('doneOrderDinner',[
      (session) =&gt; {
          session.send("Food will be on your way");
          session.replaceDialog('mainBotMenu');
      }
  ])
  
  bot.dialog('checkAge', [
      (session, result) =&gt; {
          builder.Prompts.number(session, 'Please enter your age');
      },
      (session, result) =&gt; {
          let canGetAlcohol = false;
          if(result.response &gt; 18) {
              session.send('You can get alcohol');
              canGetAlcohol = true;
          } else {
              session.send('Too young for alcohol');
          }
          const dialogResult = { resumed : true, canGetAlcohol : canGetAlcohol }
          session.endDialogWithResult(dialogResult)
      }
  ]);
  </code></pre>
  
  <p>Is there any way to achieve this without breaking the flow? Now, the message:
  'alcohol added to cart' is never printed</p>