```release-note:enhancement
resource/aws_db_instance: Add `network_type` argument
```

```release-note:enhancement
data-source/aws_db_instance: Add `network_type` attribute
```

```release-note:enhancement
resource/aws_db_subnet_group: Add `supported_network_types` argument
```

```release-note:enhancement
data-source/aws_db_subnet_group: Add `supported_network_types` attribute
```

```release-note:enhancement
data-source/aws_rds_orderable_db_instance: Add `supported_network_types` attribute
```