(maint) Restrict enabled product/dependency repos

In more recently added platforms, we are no longer providing product or
dependency repos on yum.puppetlabs.com. For any platforms that have
references to these repos where they do not exist, yum will fail when it
cannot access the repo data.

templates/mock-config.erb

@@ -105,6 +105,7 @@ mirrorlist=<%=mirrorlist_updates%>
 failovermethod=priority
 <% end %>
 
+<% if @dist == "el" && @release <= 7 %>
 # Puppetlabs Products
 [puppetlabs-products-<%=@dist%>-<%=@release%>-<%=@arch%>]
 name=yum.puppetlabs-products-<%=@dist%>-<%=@release%>-<%=@arch%>
@@ -116,6 +117,7 @@ enabled=1
 name=yum.puppetlabs-dependencies-<%=@dist%>-<%=@release%>-<%=@arch%>
 baseurl=http://yum.puppetlabs.com/<%=@dist%>/<%=prefix%><%=@release%>/dependencies/<%=@arch%>/
 enabled=1
+<% end %>
 
 <% if @dist.downcase == "el" %>
 [epel-<%=@dist%>-<%=@release%>-<%=@arch%>]