### 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)

:param gcp_scopes: Comma-separated string containing OAuth2 scopes (for ``gcp`` auth_type).
    :param azure_tenant_id: The tenant id for the Azure Active Directory (for ``azure`` auth_type).
    :param azure_resource: The configured URL for the application registered in Azure Active Directory
           (for ``azure`` auth_type).
    :param radius_host: Host for radius (for ``radius`` auth_type).
    :param radius_secret: Secret for radius (for ``radius`` auth_type).
    :param radius_port: Port for radius (for ``radius`` auth_type).
    """
    def __init__(
        self,
        url: str | None = None,
        auth_type: str = "token",
        auth_mount_point: str | None = None,
        mount_point: str | None = "secret",
        kv_engine_version: int | None = None,
        token: str | None = None,
        token_path: str | None = None,
        username: str | None = None,
        password: str | None = None,
        key_id: str | None = None,
        secret_id: str | None = None,
        role_id: str | None = None,
        kubernetes_role: str | None = None,
        kubernetes_jwt_path: str | None = "/var/run/secrets/kubernetes.io/serviceaccount/token",
        gcp_key_path: str | None = None,
        gcp_keyfile_dict: dict | None = None,
        gcp_scopes: str | None = None,
        azure_tenant_id: str | None = None,
        azure_resource: str | None = None,
        radius_host: str | None = None,