Rate limiter documentation

[kishkinova]

In order to document the InMemoryRateLimiter the configuration-rate-limiter.md was created and referenced from the configuration-routing.md.

[github-actions]

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[github-actions]

🚀 Deployed on https://672df0e89d11d3476b144145--zowe-docs-master.netlify.app

[janan07]

Reviewed and edited by doc squad