Apache Airflow Slack Provider

The Apache Airflow Slack provider package enables interaction with Slack, offering operators and hooks to send messages, upload files, and integrate with Slack workflows. It includes `SlackOperator` for the Slack API and `SlackWebhookOperator` for incoming webhooks. The current version is 9.9.0, and provider packages typically release independently of core Airflow, often aligning with Airflow's major releases or critical bug fixes.