[2127931] Change default time range on Virtualization -> Overview -> Monitoring dashboard to 30 minutes

Description of problem:
Virtualization -> Overview -> Monitoring dashboard should use the same default time range as Observe -> dashboards -> KubeVirt/Infrastructure Resources/Top Consumers dashboard uses (which is 30 minutes).

Steps to Reproduce:
1. Navigate to Virtualization/Overview/Monitoring

Actual results:
The default value of the drop-down is "Last 5 minutes".

Expected results:
The default value of the drop-down should be "Last 30 minutes".