### Is there an existing issue for this?

- [X] I have searched the existing issues

### Current Behavior

* Create any table with any records
* Do a TransactGetItems on the table
* Localstack returns 
```
ResourceNotFoundException: Cannot do operations on a non-existent table
```

### Expected Behavior

TransactGetItems should succeed.

### How are you starting LocalStack?

With a docker-compose file

### Steps To Reproduce

#### How are you starting localstack (e.g., `bin/localstack` command, arguments, or `docker-compose.yml`)

```
docker-compose up
```

`docker-compose.yml`
```
version: '3'

services:
  localstack:
    image: localstack/localstack
    environment:
      - DEFAULT_REGION=eu-west-2
      - SERVICES=dynamodb
      - DOCKER_HOST=unix:///var/run/docker.sock
    ports:
      - 4566:4566
```

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

```
#! /bin/bash
aws --endpoint-url=http://localhost:4566 dynamodb create-table --attribute-definitions AttributeName=forumId,AttributeType=S --table-name forum --key-schema AttributeName=forumId,KeyType=HASH --provisioned-throughput ReadCapacityUnits=5,WriteCapacityUnits=5 > /dev/null
aws --endpoint-url=http://localhost:4566 dynamodb put-item --table-name forum --item '{"forumId": {"S": "forum001"}, "data": {"S": "helloworld"}}' > /dev/null
aws --endpoint-url=http://localhost:4566 dynamodb get-item --table-name forum --key '{"forumId": {"S": "forum001"}}' > /dev/null
# This one fails
aws --endpoint-url=http://localhost:4566 dynamodb transact-get-items --transact-items '[{"Get": {"Key":{"forumId": {"S": "forum001"}}, "TableName": "forum"}}]' > /dev/null
```


### Environment

```markdown
- OS: MacOS 10.15.7
- LocalStack: latest, digest 843db39ff1df83fd537e15b30e39d6fb8c3590efd6bf3f6f96b1734418fbd19f
```


### Anything else?

This works in `localstack/localstack:0.14.1`
table_name = table_arn.split("/", 1)[-1]
    table_definitions = DynamoDBRegion.get().table_definitions
    if not result and table_definitions.get(table_name):
        if table_definitions[table_name].get("KinesisDataStreamDestinationStatus") == "ACTIVE":
            result = True
    cache[table_arn] = result
    return result
def get_updated_records(table_name: str, existing_items: List) -> List:
    """
    Determine the list of record updates, to be sent to a DDB stream after a PartiQL update operation.
    Note: This is currently a fairly expensive operation, as we need to retrieve the list of all items
          from the table, and compare the items to the previously available. This is a limitation as
          we're currently using the DynamoDB Local backend as a blackbox. In future, we should consider hooking
          into the PartiQL query execution inside DynamoDB Local and directly extract the list of updated items.
    """
    result = []
    stream_spec = dynamodb_get_table_stream_specification(table_name=table_name)
    key_schema = SchemaExtractor.get_key_schema(table_name)
    before = ItemSet(existing_items, key_schema=key_schema)
    after = ItemSet(ItemFinder.get_all_table_items(table_name), key_schema=key_schema)
    def _add_record(item, comparison_set: ItemSet):
        matching_item = comparison_set.find_item(item)
        if matching_item == item:
            return
        
        if comparison_set == after:
            if matching_item: