[DynamoDB] Add support for DynamoDB Table with Multi-Region Strong Consistency

**Is your feature request related to a problem?**
This is a new feature request to add support for dynamodb table with Multi-region strong consistency.

**Describe the solution you'd like**
Add ConsistencyMode as a new argument on the replicas for dynamodb table resource.

**Describe alternatives you've considered**
Using AWS update-table sdk to set the --multi-region-consistency.
