Mock failing when using with aws-sdk 2.422.0

[kvr2277]

When using aws-sdk 2.307.0 for aws-sdk-mock 4.3.1 below worked successfully.

const AWSMock = require('aws-sdk-mock');
const AWS = require('aws-sdk');
AWSMock.setSDKInstance(AWS);
AWSMock.mock('DynamoDB.DocumentClient', 'update', function (params, callback) {
	callback(null, {
		Item: { Key: 'SomeDummyValue' }, ConsumedCapacity: 2, Attributes: {
			someId: 60}
	});
});

However on changing aws-sdk to latest version of today - 2.422.0, above failed and direct call to DynamoDB is being made