fix(doc): Typo in aws-sns-lambda README.md (#374)

Fix typo and reference SnsToLambdaProps correctly.

Author: pvbouwel

source/patterns/@aws-solutions-constructs/aws-sns-lambda/README.md

@@ -45,7 +45,7 @@ _Parameters_
 
 * scope [`Construct`](https://docs.aws.amazon.com/cdk/api/latest/docs/@aws-cdk_core.Construct.html)
 * id `string`
-* props [`S3ToLambdaProps`](#pattern-construct-props)
+* props [`SnsToLambdaProps`](#pattern-construct-props)
 
 ## Pattern Construct Props
 
@@ -83,4 +83,4 @@ Out of the box implementation of the Construct without any override will set the
 ![Architecture Diagram](architecture.png)
 
 ***
-© Copyright 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+© Copyright 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.