Configuration report for DynamoDBClient

# Configuration report for DynamoDBClient

## Describe the Feature
It would be amazing to be able to access the configuration of the DynamoDBAsyncClient (and other variations).
An example of this could look like:

```
client.configurationDescription()
// "retryPolicy: , userAgentPrefix: , requestTimeout: 1 seconds, clientExecutionTimeout: 1 seconds, etc"
```

## Is your Feature Request related to a problem?
Yes, upgrading to AWS SDK v2 we see a performance hit and this would greatly benefit our investigation

## Describe alternatives you've considered
I'm not able to extract the information by debugging