### Description

Support mounting to multiple namespaces with the Hashicorp Vault Secrets Back-end

### Use case/motivation

As a data engineer I wish to utilize secrets stored in multiple mount paths (to support connecting to multiple namespaces)  without having to mount to a higher up namespace.

### Related issues

_No response_

### Are you willing to submit a 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
        with pytest.raises(VaultError, match="requires 'azure_resource'"):
            _VaultClient(
                auth_type="azure",
                azure_tenant_id="tenant_id",
                url="http://localhost:8180",
                key_id="user",
                secret_id="pass",
            )
    @mock.patch("airflow.providers.hashicorp._internal_client.vault_client.hvac")
    def test_azure_missing_tenant_id(self, mock_hvac):
        mock_client = mock.MagicMock()
        mock_hvac.Client.return_value = mock_client
        with pytest.raises(VaultError, match="requires 'azure_tenant_id'"):
            _VaultClient(
                auth_type="azure",
                azure_resource="resource",
                url="http://localhost:8180",
                key_id="user",
                secret_id="pass",
            )
    @mock.patch("airflow.providers.google.cloud.utils.credentials_provider._get_scopes")
    @mock.patch("airflow.providers.google.cloud.utils.credentials_provider.get_credentials_and_project_id")
    @mock.patch("airflow.providers.hashicorp._internal_client.vault_client.hvac")
    def test_gcp(self, mock_hvac, mock_get_credentials, mock_get_scopes):