code: function setVersioningContext(context, key, value) {
    const { versioning } = context;
  
    versioning[key] = value;
  
    if (key === 'previous') {
      process.env.EMBER_DEPLOY_PREVIOUS_VERSION = value;
    }
  
    if (key === 'current') {
      process.env.EMBER_DEPLOY_CURRENT_VERSION = value;
    }
  
    return { versioning };
  }
docs: Assigns values to the `context.versioning` object.
  
  @property setVersioningContext
  @param {Object} context
  @param {String} key
  @param {Mixed} value
  @private