Update README.md (#28022)

Add content to the pack readme.

Packs/AWS-SQS/README.md

@@ -0,0 +1,9 @@
+Amazon Simple Queue Service (SQS) is a reliable, highly-scalable hosted queuing service for storing, receiving, and sending messages between software components as they travel between applications or microservices. Amazon SQS moves data between distributed application components and helps you decouple these components. SQS offers standard best-effort ordering queues, and FIFO queues.
+
+## What does this pack do
+This pack enables you to:
+- Return the URL of an existing queue, or a list of queues.
+- Send a message to a queue.
+- Create a new standard or FIFO queue.
+- Delete a queue.
+- Purge a queue.