### Summary

`ansible-vault encrypt_string --help` shows the `--output` option but it remains without effect.

### Issue Type

Bug Report

### Component Name

ansible-vault

### Ansible Version

```console
$ ansible --version
ansible 2.9.21
  config file = /etc/ansible/ansible.cfg
  configured module search path = ['/home/elavarde/.ansible/plugins/modules', '/usr/share/ansible/plugins/modules']
  ansible python module location = /usr/lib/python3.9/site-packages/ansible
  executable location = /usr/bin/ansible
  python version = 3.9.5 (default, May 14 2021, 00:00:00) [GCC 11.1.1 20210428 (Red Hat 11.1.1-1)]
```


### Configuration

```console
$ ansible-config dump --only-changed
[... empty ...]
```


### OS / Environment

Fedora 34

### Steps to Reproduce

```shell
ansible-vault encrypt_string --ask-vault-pass --name myvar --output vault.yml 'some secret'
```


### Expected Results

Variable and its encrypted content are written to file and not to stdout _or_ the option `--output` isn't shown in the help.

Making the `--output` version working would probably be a duplicate of issue #59590, so probably removing the `--output` option which doesn't work could be a simpler step. More important for now is that it's consistent.

### Actual Results

```console
- output file isn't created/edited
- variable and its content are output to stdout
```


### Code of Conduct

- [X] I agree to follow the Ansible Code of Conduct
super(VaultCLI, self).init_parser(
            desc="encryption/decryption utility for Ansible data files",
            epilog="\nSee '%s <command> --help' for more information on a specific command.\n\n" % os.path.basename(sys.argv[0])
        )
        common = opt_help.argparse.ArgumentParser(add_help=False)
        opt_help.add_vault_options(common)
        opt_help.add_verbosity_options(common)
        subparsers = self.parser.add_subparsers(dest='action')
        subparsers.required = True
        output = opt_help.argparse.ArgumentParser(add_help=False)
        output.add_argument('--output', default=None, dest='output_file',
                            help='output file name for encrypt or decrypt; use - for stdout',
                            type=opt_help.unfrack_path())
        
        vault_id = opt_help.argparse.ArgumentParser(add_help=False)
        vault_id.add_argument('--encrypt-vault-id', default=[], dest='encrypt_vault_id',
                              action='store', type=str,
                              help='the vault id used to encrypt (required if more than one vault-id is provided)')
        create_parser = subparsers.add_parser('create', help='Create new vault encrypted file', parents=[vault_id, common])
        create_parser.set_defaults(func=self.execute_create)
        create_parser.add_argument('args', help='Filename', metavar='file_name', nargs='*')
        decrypt_parser = subparsers.add_parser('decrypt', help='Decrypt vault encrypted file', parents=[output, common])
        decrypt_parser.set_defaults(func=self.execute_decrypt)
        decrypt_parser.add_argument('args', help='Filename', metavar='file_name', nargs='*')
        edit_parser = subparsers.add_parser('edit', help='Edit vault encrypted file', parents=[vault_id, common])
        edit_parser.set_defaults(func=self.execute_edit)