Update Service Discovery doc to incorporate peer review comments

tcohen@redhat.com reviewed the API doc for integration. That doc reuses content from the 3scale Admin Portal Guide, specifically about service discovery

assemblies/service-discovery/as_service-discovery-configure.adoc ”Configuring Service Discovery”
1) Can we change the heading from “Configuring Service Discovery” to “Configuring OpenShift to enable 3scale Service Discovery“? Would it still be accurate?
2) typo in this sentence: “in” is missing
3scale users that want to use Service Discovery <in> 3scale must have access to the OpenShift cluster.

3) Configuring with RH SSO

This module starts with “After you configure 3scale discovery, …” and that jarred me because I haven’t done it yet and I thought this module was going to tell me how to do it, which it does. I would reword that to something like this: Configuration of 3scale Service Discovery with Red Hat Single Sign-On (RH SSO) causes the following behavior when a 3scale user signs in to 3scale: “

4) Also, just before 2.2.1.1, should the two entries be bullets rather than 1, 2, numbered items? Can you add information about how you decide which option to choose?

5) “Prerequisites” heading is missing - repeat some from 2.2?
“Procedure” heading is missing.

6) Using RH SSO server (Keycloak)

In the first step, will it be obvious to the reader how to create an OAuth client for 3scale? Do you need to give a sample command that shows how to do this?

In step 3, is the user supposed to replace <choose-a-client-secret> with an actual password?