[GSS](7.2.z) Clarify eap-runtime-artifacts bom in the documentation

Table 2.1. JBoss BOMs lists:
jboss-eap-javaee8
jboss-eap-javaee8-with-spring4
jboss-eap-javaee8-with-tools

But does not list eap-runtime-artifacts (which is referenced earlier). It would be good to include eap-runtime-artifacts in the Table 2.1 and clarify how it is different from the other boms listed

https://access.redhat.com/documentation/en-us/red_hat_jboss_enterprise_application_platform/7.2/html-single/development_guide/index#manage_project_dependencies