grafana update to 7.2.1-bb.2

Package Merge Request

Package Changes

Grafana/Istio: Stop exposing grafana virtualservice's /metrics endpoint

Package MR

big-bang/product/packages/grafana!51 (merged)

For Issue

Closes https://repo1.dso.mil/big-bang/product/packages/grafana/-/issues/19

Upgrade Notices

(Include any relevant notes about upgrades here or write "N/A" if there are none)