msk ClusterConfiguration cannot be created

## :rocket: Feature Request

### General Information
* [ ] :wave: I may be able to implement this feature request
* [ ] :warning: This feature might incur a breaking change

### Description
cdk-msk cannot create the ARN object referenced by the MSK constructor prop 'configurationInfo', the API can only reference a previously created ARN and revision which is provisioned from CLI command 'aws kafka create-configuration ... '

There should be a way to create and update the referenced ClusterConfiguration.

The current workflow is:

1. create a text file, containing props like

auto.create.topics.enable = false
min.insync.replicas = 2
zookeeper.connection.timeout.ms = 1000

2. upload this using 'aws kafka create-configuration', which returns a ARN like:

arn:aws:kafka:eu-central-1:999999999999:configuration/MyKafkaClusterConfig/uuid...

3. Reference the returned ARN in the 'configurationInfo' property for the MSK builder.

const kafka = new msk.CfnCluster(this, 'mykafka', {
// reference the properties ARN
configurationInfo: {
arn: 'arn:aws:kafka:eu-central-1:999999999999:configuration/MyKafkaClusterConfig/uuid...3',
revision: 1,
},
});

I would like to define my configuration properties in setp 1 in the cdk app/stack, rather than rely on the external mechanism to create those properties.

### Proposed Solution
A constructor / builder for the arn:aws:kafka object which is then referenced by to configurationInfo

### Environment

- **CDK CLI Version:** 1.6.0
- **Module Version:** 1.6.0
- **OS:** Windows 10
- **Language:** TypeScript

### Other information

Start at the msk.CfnCluster configurationInfo property and compare it with the AWS Kafka create-configuration workflow described in the issue. Determine how a CDK app could define the configuration properties and obtain the ARN and revision; done means the cluster can reference a configuration created and updated through CDK rather than an external CLI command.

Written by the indexing model from the issue text.