AWS Config Organizational Custom Rules using Guard Custom policy

### Name of the resource

AWS::Config::OrganizationConfigRule

### Resource name

_No response_

### Description

We can create an organizational config rule (organization-custom-policy-rule-metadata) using the CLI
```
$ aws configservice put-organization-config-rule --organization-config-rule-name test-1 --organization-custom-policy-rule-metadata PolicyRuntime="guard-2.x.x",PolicyText="let var=5",OrganizationConfigRuleTriggerTypes=ConfigurationItemChangeNotification
```

It's also possible with some SDKs like boto3:
```
response = client.put_organization_config_rule(
OrganizationConfigRuleName='test-rule-2',
OrganizationCustomPolicyRuleMetadata={
'OrganizationConfigRuleTriggerTypes': ['ConfigurationItemChangeNotification'],
'PolicyRuntime': 'guard-2.x.x',
'PolicyText': 'let test = 123'
}
)
```

Unfortunately it's not supported by CloudFormation.

### Other Details

_No response_

Start by comparing the CloudFormation representation of AWS::Config::OrganizationConfigRule with the AWS Config put-organization-config-rule CLI and boto3 examples in the issue. Determine the CloudFormation metadata needed for organization-custom-policy-rule-metadata, and consider the work complete when this Guard custom policy rule can be expressed and deployed through CloudFormation.

Written by the indexing model from the issue text.