title: How do I add environment variables to a container with azure build yml?
body: <p>Trying to deploy an app to kubernetes using azure. I have a build pipeline yml file and in the pipeline i've set a variable called "discordToken". I tried setting it two different ways, one is called discordToken and the other is MY_MAPPED_ENV_VAR. 
  in my node project i'm doing</p>
  
  <pre><code>console.log( process.env.discordToken )
  console.log( process.env.MY_MAPPED_ENV_VAR )
  </code></pre>
  
  <p>but everything keeps coming back as undefined. </p>
  
  <pre><code>stages:
  - stage: Build
    displayName: Build stage
    jobs:  
    - job: Build
      displayName: Build
      pool:
        vmImage: $(vmImageName)
        environment:
          discordToken: $(discordToken)
      steps:
      - powershell: |
        env:
          MY_MAPPED_ENV_VAR: $(discordToken)
      - task: Docker@2
        displayName: Build and push an image to container registry
        inputs:
          command: buildAndPush
          repository: $(imageRepository)
          dockerfile: $(dockerfilePath)
          containerRegistry: $(dockerRegistryServiceConnection)
          tags: |
            $(tag)
  </code></pre>
  
  <p>How should i be setting the environment variables? </p>