### Apache Airflow version

2.6.1

### What happened

Trying to connect to Vault using `auth_type` = `aws_iam`. I am receiving the following error: `AttributeError: 'Client' has no attribute 'auth_aws_iam'`. Looking through [the code](https://github.com/apache/airflow/blob/main/airflow/providers/hashicorp/_internal_client/vault_client.py#L303), you are using `client.auth_aws_iam`, but the [HVAC docs](https://hvac.readthedocs.io/en/stable/usage/auth_methods/aws.html#caveats-for-non-default-aws-regions) use `client.auth.aws.iam_login`. You should also add support for `boto3.Session()` to use role based access.

### What you think should happen instead

Airflow should authenticate to Vault using AWS auth.

### How to reproduce

Setup a secrets backend of `airflow.providers.hashicorp.secrets.vault.VaultBackend` and set `auth_type` = `aws_iam`. It will error out saying that the client doesn't have an attribute named `auth_aws_iam`.

### Operating System

Docker

### Versions of Apache Airflow Providers

_No response_

### Deployment

Official Apache Airflow Helm Chart

### Deployment details

_No response_

### Anything else

_No response_

### Are you willing to submit PR?

- [ ] Yes I am willing to submit a PR!

### Code of Conduct

- [X] I agree to follow this project's [Code of Conduct](https://github.com/apache/airflow/blob/main/CODE_OF_CONDUCT.md)

mock_client = mock.MagicMock()
        mock_hvac.Client.return_value = mock_client
        vault_client = _VaultClient(
            auth_type="ldap",
            username="user",
            password="pass",
            auth_mount_point="other",
            url="http://localhost:8180",
        )
        client = vault_client.client
        mock_hvac.Client.assert_called_with(url="http://localhost:8180")
        client.auth.ldap.login.assert_called_with(username="user", password="pass", mount_point="other")
        client.is_authenticated.assert_called_with()
        assert 2 == vault_client.kv_engine_version
    @mock.patch("airflow.providers.hashicorp._internal_client.vault_client.hvac")
    def test_radius_missing_host(self, mock_hvac):
        mock_client = mock.MagicMock()
        mock_hvac.Client.return_value = mock_client
        with pytest.raises(VaultError, match="radius_host"):
            _VaultClient(auth_type="radius", radius_secret="pass", url="http://localhost:8180")
    @mock.patch("airflow.providers.hashicorp._internal_client.vault_client.hvac")
    def test_radius_missing_secret(self, mock_hvac):
        mock_client = mock.MagicMock()
        mock_hvac.Client.return_value = mock_client
        with pytest.raises(VaultError, match="radius_secret"):
            _VaultClient(auth_type="radius", radius_host="radhost", url="http://localhost:8180")
    @mock.patch("airflow.providers.hashicorp._internal_client.vault_client.hvac")
    def test_radius(self, mock_hvac):