Update the product reference (#895)

Co-authored-by: GitHub Actions <[email protected]>

Author: jmagak

artifacts/attributes.adoc

@@ -33,6 +33,7 @@
 :openshift-cli: pass:quotes[OpenShift CLI (`oc`)]
 :rhsso-brand-name: Red Hat Single-Sign On
 :rhsso: RHSSO
+:keycloak-version: 18.x
 
 // Partner Platforms
 :aws-brand-name: Amazon Web Services

artifacts/rhdh-plugins-reference/keycloak/keycloak-plugin-admin.adoc

@@ -1,5 +1,5 @@
 [id="rhdh-keycloak_{context}"]
-= Installing and configuring Keycloak 
+= Installing and configuring Keycloak
 
 The Keycloak backend plugin, which integrates Keycloak into {product-short}, has the following capabilities:
 
@@ -8,7 +8,7 @@ The Keycloak backend plugin, which integrates Keycloak into {product-short}, has
 
 [NOTE]
 ====
-The supported Keycloak version is `18.x`.
+The supported {rhsso-brand-name} ({rhsso}) version is {keycloak-version}.
 ====
 
 == Installation