```release-note:enhancement
resource/aws_config_config_rule: Add `source.custom_policy_details` argument.
```

```release-note:enhancement
resource/aws_config_config_rule: Add plan time validation for `source.source_detail.event_source` and `source.source_detail.message_type`.
```

```release-note:enhancement
resource/aws_config_config_rule: Make `source.source_identifier` optional.
```