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# Type of request: This is a ...

[ ] bug report
[X ] feature request

# Detailed description

I'm using localstack to create a dynamoDb table locally with a dynamodb stream and a flink application consuming data from the stream
The shardId created in localstack follows this format

shardId-000000000000-798cedd84a2953c5af70a131f8701f35

Flink expects this format
shardId-00000001592367572726-07776efd

The difference is just after the prefix shardId.
Normally the real shardId created by amazon use is composed by shardId prefix, 20-digit timestamp and 0-36 or more characters separated by '-'

The current shardId format is not valid for flink applications and it's not following the real pattern used by amazon

## Expected behavior

ShardId must follow the pattern
shardId prefix, 20-digit timestamp and 0-36 or more characters separated by '-'

## Actual behavior

The shardId follows the pattern
shardId prefix, 12 0s and 33 characters separated by '-'

# Steps to reproduce

Create a dynamodb table

## Command used to start LocalStack

I'm using docker and docker compose to run localstack


## Client code (AWS SDK code snippet, or sequence of "awslocal" commands)

aws --endpoint-url=http://localhost:4566 dynamodb create-table \
    --table-name temp4 \
    --attribute-definitions AttributeName=partition_key,AttributeType=S AttributeName=sort_key,AttributeType=S \
    --key-schema AttributeName=partition_key,KeyType=HASH AttributeName=sort_key,KeyType=RANGE \
    --provisioned-throughput ReadCapacityUnits=100,WriteCapacityUnits=100 \
    --stream-specification StreamEnabled=true,StreamViewType=NEW_AND_OLD_IMAGES


@classmethod
    def setUpClass(cls):
        cls.dynamodb = aws_stack.connect_to_resource('dynamodb')
    def test_non_ascii_chars(self):
        aws_stack.create_dynamodb_table(TEST_DDB_TABLE_NAME, partition_key=PARTITION_KEY)
        table = self.dynamodb.Table(TEST_DDB_TABLE_NAME)
        
        items = {
            'id1': {PARTITION_KEY: 'id1', 'data': 'foobar123 ✓'},
            'id2': {PARTITION_KEY: 'id2', 'data': 'foobar123 £'},
            'id3': {PARTITION_KEY: 'id3', 'data': 'foobar123 ¢'}
        }
        for k, item in items.items():
            table.put_item(Item=item)
        for item_id in items.keys():
            item = table.get_item(Key={PARTITION_KEY: item_id})['Item']
            # ne
            item1 = json_safe(item)
            item2 = json_safe(items[item_id])
            self.assertEqual(item1, item2)
        # cl
        delete_table(TEST_DDB_TABLE_NAME)
    def test_large_data_download(self):