Add functionality to download a file

[edif2008]

Summary

Starting with Connect 1.3.0, the users can get files that are stored in an Item. Connect Node SDK should enable the users to do that.

In this issue, we will enable the user to download a file stored in 1Password.

Tasks to be done

• Implement downloadFile function in the Items class in src/lib/resources.ts. The API endpoint that this function needs to call is v1/vaults/vaultId/items/itemId/files/fileId/content. You'll have to figure out the object type the promise expects.

  /**
   * Download an Item's File in the provided path.
   *
   * @param {string} vaultId
   * @param {string} itemQuery
   * @param {string} fileId
   * @param {string} targetDirectory
   * @param {boolean} overwrite
   * @returns {Promise<string>}
   * @private
   */
  private async getFileContent(
           vaultId: string,
           itemQuery: string,
           fileId: string,
           targetDirectory: string,
           overwrite: boolean,
       ): Promise<string> {
       // functionality
  }

  Note: Feel free to place this functionality in a separate class (e.g. Files) if you feel it's more suitable. This is just a suggested approach.
• Implement downloadFile function in OPConnect class in src/lib/op-connect.ts:

  /**
   * Download an Item's File in the provided path.
   *
   * @param {string} vaultId
   * @param {string} itemQuery
   * @param {string} fileId
   * @returns {Promise<string>}
   */
  public async downloadFile(vaultId: string, itemQuery: string, fileId: string. targetDirectory: string, overwrite: boolean): Promise<string> {
        return await this.items.getFileContent(vaultId, itemQuery, fileId, targetDirectory, overwrite);
  }

• Add a test for the new function in __test__/op-connect.test.ts. This may be a tricky one.

  test("downloadFile", async () => {
      // actual test here
  }

[edif2008]

This issue is blocked by #62

[volodymyrZotov]

Feature is unblocked now and can be implemented. Help from the community is very warm welcome!