Describe the issue:
-------------------
Correct the "Red Hat Ceph Storage documentation" hyper link in the Scaling storage guide in chapter 1.
We support RHCS 5.3 with RHODF 4.12 in external mode[1] Hence, the hyper link should point to RHCS 5 instead of RHCS 4 documentation link.

```
For scaling your storage in external mode, see Red Hat Ceph Storage documentation. <---- hyper link in chapter 1.
```

[1] https://access.redhat.com/articles/4731161

Suggestions for improvement:
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Change the hyper link to point to RHCS 5 documentation deck instead of RHCS 4
i.e it should point to ---> https://access.redhat.com/documentation/en-us/red_hat_ceph_storage/5

Document URL:
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https://access.redhat.com/documentation/en-us/red_hat_openshift_data_foundation/4.12/html-single/scaling_storage/index#scaling-overview_rhodf

Chapter/Section Number and Title:
---------------------------------
Chapter 1. Introduction to scaling storage

Product Version:
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RHODF 4.12

Any other versions of this document that also needs this update:
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No