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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


return str(uuid.uuid4())[0:8]
def long_uid():
    return str(uuid.uuid4())
def json_safe(item):
    """ return a copy of the given object (e.g., dict) that is safe for JSON dumping """
    try:
        return json.loads(json.dumps(item, cls=CustomEncoder))
    except Exception:
        item = fix_json_keys(item)
        return json.loads(json.dumps(item, cls=CustomEncoder))
def fix_json_keys(item):
    """ make sure the keys of a JSON are strings (not binary type or other) """
    item_copy = item
    if isinstance(item, list):
        item_copy = []
        for i in item:
            item_copy.append(fix_json_keys(i))
    if isinstance(item, dict):
        item_copy = {}
        for k, v in item.items():
            item_copy[to_str(k)] = fix_json_keys(v)
    return item_copy
def canonical_json(obj):