Add example CLI for configuration of `enable-amq1-prefix`

When we added documentation about the `enable-amq1-prefix` configuration attribute, we did not include an example CLI command illustrating the configuration. The attribute value is a boolean, which has caused some user confusion.

We should add an example CLI command to clarify.

See https://issues.redhat.com/browse/EAP7-1244?focusedCommentId=15848562&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-15848562