Client examples that use the generic client have been added (#2799)

## Motivation and Context
Example code that demonstrates the usage of pokemon-service-client. 

## Description

Examples have been added that show how to add middleware, configure
retries, timeouts, and handle errors when calling operations on the
pokemon-service.


_By submitting this pull request, I confirm that you can use, modify,
copy, and redistribute this contribution, under the terms of your
choice._

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Co-authored-by: Fahad Zubair <fahadzub@amazon.com>