I had this after reading #12537 and #9047. Currently `DockerOperator`’s `volumes` argument is passed directly to docker-py’s `bind` (aka `docker -v`). But `-v`’s behaviour has long been problematic, and [Docker has been pushing users to the new `--mount` syntax instead](https://docs.docker.com/storage/bind-mounts/#choose-the--v-or---mount-flag). With #12537, it seems like `-v`’s behaviour is also confusing to some Airflow users, so I want to migrate Airflow’s internals to `--mount`.

However, `--mount` has a different syntax to `-v`, and the behaviour is also slightly different, so for compatibility reasons we can’t just do it under the hood. I can think of two possible solutions to this:

A. Deprecate `volumes` altogether and introduce `DockerOperator(mounts=...)`

This will emit a deprecation warning when the user passes `DockerOperator(volumes=...)` to tell them to convert to `DockerOperator(mounts=...)` instead. `volumes` will stay unchanged otherwise, and continue to be passed to bind mounts.

`mounts` will take a list of [`docker.types.Mount`](https://docker-py.readthedocs.io/en/stable/api.html#docker.types.Mount) to describe the mounts. They will be passed directly to the mounts API. Some shorthands could be useful as well, for example:

```python
DockerOperator(
    ...
    mounts=[
        ('/root/data1', './data1'),  # Source and target, default to volume mount.
        ('/root/data2', './data2', 'bind'),  # Bind mount.
    ],
)
```

B. Reuse `volumes` and do introspection to choose between binds and mounts

The `volumes` argument can be augmented to also accept `docker.types.Mount` instances, and internally we’ll do something like

```python
binds = []
mounts = []
for vol in volumes:
    if isinstance(vol, str):
        binds.append(vol)
    elif isintance(vol, docker.types.Mount):
        mounts.append(vol)
    else:
        raise ValueError('...')
if binds:
    warnings.warn('...', DeprecationWarning)
```

and pass the collected lists to binds and mounts respectively.

I’m very interested in hearing thoughts on this.


**Are you willing to submit a PR?**
Yes

**Related Issues**

* #12537: Confusing on the bind syntax.
* #9047: Implement mounting in `DockerSwarmOperator` (it’s a subclass of `DockerOperator`, but the `volumes` option is currently unused).

tests/providers/docker/operators/test_docker.py
def setUp(self):
        self.tempdir_patcher = mock.patch('airflow.providers.docker.operators.docker.TemporaryDirectory')
        self.tempdir_mock = self.tempdir_patcher.start()
        self.tempdir_mock.return_value.__enter__.return_value = '/mkdtemp'
        self.client_mock = mock.Mock(spec=APIClient)
        self.client_mock.create_container.return_value = {'Id': 'some_id'}
        self.client_mock.images.return_value = []
        self.client_mock.attach.return_value = ['container log']
        self.client_mock.logs.return_value = ['container log']
        self.client_mock.pull.return_value = {"status": "pull log"}
        self.client_mock.wait.return_value = {"StatusCode": 0}
        self.client_mock.create_host_config.return_value = mock.Mock()
        self.client_class_patcher = mock.patch(
            'airflow.providers.docker.operators.docker.APIClient',
            return_value=self.client_mock,
        )
        self.client_class_mock = self.client_class_patcher.start()
    def tearDown(self) -> None: