### Description

Currently some code in RDS Operators use boto waiters and some uses a custom `_await_status`, the former is preferred over the later (waiters are vetted code provided by the boto sdk, they have features like exponential backoff, etc). See [this discussion thread](https://github.com/apache/airflow/pull/27076#discussion_r997325535) for more details/context.

### Use case/motivation

_No response_

### Related issues

_No response_

### Are you willing to submit a PR?

- [ ] Yes I am willing to submit a PR!

### Code of Conduct

- [X] I agree to follow this project's [Code of Conduct](https://github.com/apache/airflow/blob/main/CODE_OF_CONDUCT.md)

"""
    Creates an RDS event notification subscription
    .. seealso::
        For more information on how to use this operator, take a look at the guide:
        :ref:`howto/operator:RdsCreateEventSubscriptionOperator`
    :param subscription_name: The name of the subscription (must be less than 255 characters)
    :param sns_topic_arn: The ARN of the SNS topic created for event notification
    :param source_type: The type of source that is generating the events. Valid values: db-instance |
        db-cluster | db-parameter-group | db-security-group | db-snapshot | db-cluster-snapshot | db-proxy
    :param event_categories: A list of event categories for a source type that you want to subscribe to
        `USER Events <https://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/USER_Events.Messages.html>`__
    :param source_ids: The list of identifiers of the event sources for which events are returned
    :param enabled: A value that indicates whether to activate the subscription (default True)l
    :param tags: A list of tags in format `[{"Key": "something", "Value": "something"},]
        `USER Tagging <https://docs.aws.amazon.com/AmazonRDS/latest/UserGuide/USER_Tagging.html>`__
    :param wait_for_completion:  If True, waits for creation of the subscription to complete. (default: True)
    """
    template_fields = (
        "subscription_name",
        "sns_topic_arn",
        "source_type",
        "event_categories",
        "source_ids",
        "tags",
    )
    def __init__(