lib/classes/PluginManager.js/PluginManager/validateServerlessConfigDependency
class PluginManager:  validateServerlessConfigDependency(command) {
    if ('configDependent' in command && command.configDependent) {
      if (!this.serverlessConfigFile) {
        const msg = [
          'This command can only be run in a Serverless service directory. ',
          "Make sure to reference a valid config file in the current working directory if you're using a custom config file",
        ].join('');
        throw new this.serverless.classes.Error(msg);
      }
    }
  }