Technical the documentation for including 3scale is correct - see https://maistra.io/docs/installation/installation-options/#_3scale

However it is not noted anywhere in the docs that the `threeScale:` block should sit as a sibling of the `istio:` block and not indented as per the examples with kiali and jaeger etc.

dfenness@redhat.com,kevinconner_jira I'm suggesting we update the example in https://maistra.io/docs/installation/installation-options/#_customizing_the_installation even if it means defaulting the enabled to false, just so it is clear to the reader how the yams should structured to include (or not) the 3scale adapter