code: function updateFile(params, cb) {
    var resourcePath = config.addURIParams(constants.FORMS_BASE_PATH + "/submissions/:id/fields/:fieldId/files/:fileId", params);
    var method = "PUT";
    var data = params.fileDetails;
  
    params.resourcePath = resourcePath;
    params.method = method;
    params.data = data;
  
    params.fileRequest = true;
    params.fileUploadRequest = true;
  
    mbaasRequest.admin(params, cb);
  }
docs: Update A File For A Submission
  @param {object}      params
  @param {string}      params.id                   The submission ID (The submission should already exist)
  @param {string}      params.domain               The Domain
  @param {string}      params.environment          The Environment ID to upload To
  @param {string}      params.fieldId              The ID of the file field the file should be associated with.
  @param {string}      params.fileId               The ID of the file. It must already exist
  @param {object}      params.fileDetails          The Details of the file to be uploaded
  @param {string}      params.fileDetails.stream   A Readable file stream
  @param {string}      params.fileDetails.name     The name of the file
  @param {number}      params.fileDetails.size     The size of the file (In Bytes)
  @param {string}      params.fileDetails.type     The mime type of the file
  @param cb