Fix bug where performance pages would not appear
Fix bug where performance pages would not appear

Behaviour before: For Middleware Servers, Middleware Messagings and
Middleware Datasources, clicking on "Monitoring > Utilization" button,
utilization page was not being open, showing server details page without menu
items instead.

This fixes the problem by check for the correct methods when dispatching
from GenericShowMixin.

ManageIQ/manageiq-ui-classic,ManageIQ/manageiq-ui-classic,ManageIQ/manageiq-ui-classic,ManageIQ/manageiq-ui-classic