title: Marking variables in variables groups as secrets makes them invisible
body: <p>I have a case that marking variables as secrets loses their value in Release task, please allow me to elaborate further. </p>
  
  <p>Please find below screenshot of Terraform Service principal</p>
  
  <p><a href="https://i.stack.imgur.com/boMfu.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/boMfu.png" alt="enter image description here"></a></p>
  
  <p>The above one works as variables are available in pipeline.</p>
  
  <p>Take scenario, where they are secret and locked.</p>
  
  <p><a href="https://i.stack.imgur.com/mGYna.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/mGYna.png" alt="enter image description here"></a></p>
  
  <p>Now, run the pipeline and it reports required variable not set.</p>
  
  <p><a href="https://i.stack.imgur.com/O254v.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/O254v.png" alt="enter image description here"></a></p>
  
  <p>I have added a step to echo these variables, just to see if I can see them, here is the Release task:
  <a href="https://i.stack.imgur.com/CNW3m.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/CNW3m.png" alt="enter image description here"></a></p>
  
  <p>I "assume" *** means actual echo, so they word in echo statement.</p>
  
  <p>Not able to understand why the behavior is different:</p>
  
  <ol>
  <li>When in plain text, they are available in pipeline</li>
  <li>When marked as secret they are not available.</li>
  </ol>
  
  <p>How to make them available in pipeline?</p>
  
  <h3>Updates</h3>
  
  <p>doing something like this: </p>
  
  <pre><code>Terraform plan -out main.plan -var "ARM_SUBSCRIPTION_ID=$(TF_VAR_ARM_SUBSCRIPTION_ID)" "ARM_CLIENT_ID=$(TF_VAR_ARM_CLIENT_ID)" "ARM_CLIENT_SECRET=$(TF_VAR_ARM_CLIENT_SECRET)" "ARM_TENANT_ID=$(TF_VAR_ARM_TENANT_ID)" It reports: 2019-03-07T00:21:19.7692360Z ##[command]"terraform" plan -out main.plan -var "ARM_SUBSCRIPTION_ID=***" "ARM_CLIENT_ID=***" "ARM_CLIENT_SECRET=***" "ARM_TENANT_ID=***" -input=false -no-color 
  </code></pre>
  
  <p>get error</p>
  
  <pre><code>2019-03-07T00:21:19.8504985Z Too many command line arguments. Configuration path expected. 
  </code></pre>