Developer notes
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Hi Canva, I decided to define the Queue Service interface to include the queue create, list, get (url) and delete methods because
as a fake for SQS they seems pretty sensible behaviours to include alongside the ususal push, pull and delete message.

- I didn't notice until implementing the adapter in question 4 that deleteMessage doesn't return a result, I though it
    so that is an inaccuracy of the interface

If I had more time

   - I would add validation to the fields for allowable characters in message body as specified by SQS doco

   - I would validate all other string arguments i.e. queue name (ends in .fifo), url, receipt id

   - I would test the thread safety around the queue create, list, get url and delete methods

   - I would also do more concurrency testing

   - I would try to test behaviours or order and delivery better