Update registry1.dso.mil/ironbank/opensource/grafana/grafana Docker tag to v10.3.1

This MR contains the following updates:

Package	Type	Update	Change
registry1.dso.mil/ironbank/opensource/grafana/grafana		minor	10.2.3 -> 10.3.1
registry1.dso.mil/ironbank/opensource/grafana/grafana	ironbank-base	minor	10.2.3 -> 10.3.1
registry1.dso.mil/ironbank/opensource/grafana/grafana	final	minor	10.2.3 -> 10.3.1

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