[RFC] Supporting Queues / Messaging Pipelines across Cloud Providers (Ex: AWS SQS)

## Feature Request

A commonly used feature in Cloud Platforms is their message-passing/queueing services, such as
* [AWS](https://aws.amazon.com/sqs/): SQS
* [Azure](https://learn.microsoft.com/en-us/azure/service-bus-messaging/service-bus-azure-and-service-bus-queues-compared-contrasted): [Service-Bus, Storage Queues]
* [GCP](https://cloud.google.com/pubsub/docs/choosing-pubsub-or-cloud-tasks): [Cloud Tasks, Cloud Pub-Sub]

These are often used in conjunction with their other services, such as Storage (Ex: to send a message-notification automatically when a new file is uploaded to a Container/Bucket) and Compute (Ex: To pass information between different compute instances, or to take an action whenever a new file is uploaded to Storage). However, it is a pain right now to deal with the different CSP's syntaxes for using these queues, and would be convenient if we could centralize how we carry out at least basic operations like:
1. Read `n` messages from queue
2. Add new messages into the queue
3. Flush the queue / Delete `n` items from the queue

Das Issue nennt keine Repository-Dateien, Tests oder Einstiegspunkte. Beginne damit, Libclouds Provider-Abstraktionen und vorhandene übergreifende Resource-APIs zu lokalisieren, und vergleiche dann die für AWS, Azure und GCP aufgeführten grundlegenden Queue-Operationen. Der Abschluss sollte ein abgestimmtes Design sowie Unterstützung für das Lesen, Hinzufügen und Löschen von Nachrichten über die Ziel-Provider hinweg umfassen.

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