code: function strFromEnvironmentVarSetting(functionsVar, envVar) {
    if (!process.env[envVar]) {
      const msg = `${envVar} does not exist on within environment variables`
      warn(msg)
      return ''
    }
    return `${functionsVar}="${process.env[envVar]}"`
  }
docs: Build a string from mapEnv setting
  @param {String} functionsVar - Name of variable within functions
  @param {String} envVar - Variable within environment