(aws-rds): DatabaseClusterFromSnapshot no credentials property

Would it be possible to add a credentials property/parameter to DatabaseClusterFromSnapshot? It should be similar to the credentials option in DatabaseInstanceFromSnapshot.

### Use Case

Now when you restore a cluster from snapshot you don't have the master user in aws secrets manager

### Proposed Solution

See the description.

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This is a :rocket: Feature Request

Start with the DatabaseClusterFromSnapshot entry point and compare its options with the credentials option on DatabaseInstanceFromSnapshot. Trace the related AWS RDS behavior and existing tests, then confirm that restoring a cluster from a snapshot can accept credentials and that the master user is available in AWS Secrets Manager as described.

Written by the indexing model from the issue text.